Frequently Asked Questions

Frequently Asked Questions

Over the years I have been asked lots of questions from discus keepers which I have included here. Some questions are from the talks I have given at fish clubs, some from the readers of my regular articles, and some from my own customers and Internet forums. Nine times out of ten, these questions answer most problems, or queries that are raised.

Finicky Feeder

Q: I have a discus, which is spitting food out.  He seems to be trying to eat the same piece several times and spitting it out again. This is the case for granules, which are slow sinking for discus, flake food, and freeze dried bloodworms. Other than this he seems very healthy. Good colour and is bullying the other three discus (smaller) in the tank. Any advice? Will this type of thing just come and go? It’s only been happening for one day. Before this he has eaten lots. I understand there is a parasite that can cause this, but it would come with white excretions. No sign of this yet. Basically I’m looking to see if there is something that can be done I would like to get into it early, otherwise if it is something which just happens from time to time I’ll know to just monitor.

A: This is a very common problem with some discus. Just like some humans, discus can be finicky feeders and appear to not eat very much and cause alarm bells ringing with worried keepers. I often hear discus keepers say; ‘My discus have not fed now for three months’. If it did not feed for three months it would not be still swimming around the tank, it simply must be eating something. It is very possible for a discus to live to a good old ripe age and appear to eat nothing. It will just pick at a few pieces of food and be fine. Again, just like some humans. You are right though; it may be possible that some type of parasite has caused the discus to act like this, partially if this behaviour has never happened before. In this case the best thing to do is to treat for parasites inside and out just in case as a precaution. Treat with a three day course of Octozin made by waterlife and at the same time treat with wormer plus to rid the discus of any parasites inside and out that may possibly be causing the problem just in case. It would do no harm to try this anyway as a health boost  from time to time.

Dominant Discus

Q: I have had a discus for about six or seven months now. He has got to be about 5 or 6 inches long, very healthy and nice. I went and bought  a new discus two days ago – which was probably a mistake – the old discus constantly chases the new one. Well I say constantly – but really it is when he finds him. The new one hides away as the tank is fairly well planted, but he finds him every ten minutes or so. He has nipped his rear fin, which is now damaged. Thing is, the new discus’s fins aren’t overly clamped, and he is still eating. But clearly something needs to be done. I spoke to the shop I bought him off, and they won’t accept the discus back, though they offered to take my larger one and swap it for another small one. The idea being that then I would have two new discus in the tank with nether being territorial. It seems to me though, that the shop will get the better end of this deal. Are there any other ideas you have for this aggression?

A: This is a very common problem when discus are kept on their own, or in a small group of under six in number individuals. Discus are typical cichlids and will become very territorial when breeding, or if they are kept alone and new fish are added. Sometimes you can even get one that will turn and dominate the tank in a new group that has been added together. Although it seems the shop you bought him off are getting a good deal by exchanging a small discus, for a large one. This is normally the best option when this happens. Plus they may get problems re-homing him, or getting him to settle into a new group themselves. With any new discus going into a new tank, where other have become established, it is a good idea to move around all the aquascaping, plants, rocks, bogwood, in fact anything to upset the territory of the old fish.  Then with a new lay out of territory, they should settle down well together. If you wanted to try something else, you could try this plan and add four more new discus at once making the magic number of six discus in the group. But this of course depends on how big your tank is, which you have not mentioned. With more discus in the group, the bully should not target just one individual and settle down. Although this can never be guaranteed. But I have always found if room allows, the bigger the group, the better they seem to get on.

Discus Worms

Q: One of my discus has not been eating properly and doing white poo, (white faeces). It is long, stringy and jelly looking, so I thought it might have constipation. I’ve heard that epsom salt was good for discus so ordered some and it actually arrived today. I was told one tablespoon per 10 gallons, is the right before I add any?

A: This is a very common problem with discus, and at first glance looks like worms. The discus keeper then uses aquatic fish wormers, and when it does work they start shouting ‘it doesn’t work’!! When the problem is not resolved. The problem here is an intestinal bacterial parasite problem. So no aquatic worming treatments on the market will fix this alone. I have used two methods in the past to cure this problem. The first way is to use a full dose of wormer plus on day one with a full dose of interpet number nine anti internal bacteria, then use half a dose of both every day until the problem is solved, which can take up to a week depending on how severe the infestation is. My second way is to treat with ‘Octozin’ made by water life, and do a three-day treatment. A second dose is normally needed in heavy infestations. So after the three-day course, do a 35% water change on day four. On day five start a second three-day course again, this usually works. Epsom salts is not a good idea in a discus tank unless you need to harden the water, as this is what it will do. By the sound of the dosage it may be that you are getting confused with cooking salt. With a problem such as this, cooking salt or aquatic can be added to help speed up this sort of problem. Because salt kills bacteria, this will help the medication off to a good start. But remember, salt can harden the water, so keep to the heaped tablespoonful for every ten-gallons of aquarium water, and no more than that. Salt can also be used with the first method with the wormer plus method also.

New To Discus

Q: I am new to keeping discus, from what I have read so far is seems there are differing opinions when it comes to introducing new discus into your tank. I have read two different options. Equalise the temperature and PH by floating the bag of water every 20 minutes until after about an hour you can put the new discus into the tank. But what I have also read is keeping discus in bags for any length of time stresses them out so it’s best to let them straight out. Please could you clarify which is best for discus? I don’t want to say which is right or wrong because I know that there sometimes be more than one way of doing things, when it comes to our hobby.

A: When introducing new discus into my tanks I find the best way is to get the fish into there new inverament as soon as possible. The reason is that discus find it more stressful floating around the tank in a bag when they can see cover and somewhere to go and feel safe, and sometimes panic trying to get out. So, the sooner they can be released and get to that cover or behind some bogwood etc, until they feel safe to come out into the new tank, the better. In the past I have seen discus jump out of the bags onto the floor and hurt themselves trying to get out. As you rightly say, many discus keepers say different things and with the discus world it has always been the same. My method is to cut the top of the bag off and place the bag onto the top of the water in the tank. Let some of your water into the bag, and then let some back out. This will mix the two types of water together, but not too quickly. Do this about 6-8 times and let the discus out into the new tank to find safe refuge. Your tank water should match that of the dealers anyway, and should not be too far out. This I have always been the best, quickest and safe way to add new discus to a new tank.

Keeping The King

Q: I would love to eventually keep discus. I have a 486-litre tank (106 UK gallons) that I would like to keep them in when I do get them. Are there any brilliant sites to read or books to get? I’ve had a look around but the more in-depth information seems pretty difficult to find, I’m a planner and , would I need to like to know lots about any animals I keep a long time before I get them. I’ve heard lots of conflicting advice too, for example can they or can’t they live with small fish neons? My favourite is the wild type colouring. Is it possible to get these that home bred rather than wild caught? If I get a group of six would I need to balance the sexes or could I get very ones and watch them grow?

A: You should be able to find plenty of information on the internet, but as you say the advice offered will be conflicting. The reason for this is that any adice on the internet is of many peoples opinion, and may not always be quite correct. A good book to read should be the one you are now reading which has already been nick-named the new discus bible by the people who had an early look before publishing. My old friend from Singapore Andrew Soh’s book the naked truth is also another good book to read, offering a different view on this fantastic fish. Or an old favourite of mine is; Discus….as a hobby by Jim E Quarles. This is a short and sweet book, and straight to the point covering everything briefty about discus. If the neon’s are not too small they can be kept with discus. Even though discus can look large, they have small mouths, so will not be interested in good sized tetras. F1 discus (first line bred from wild discus) are sometimes available from breeders, although most these days are imported in from South America and settle into home aquariums very quickly if the conditions are right. A group of six is the perfect number of discus to keep as a minimum. Being a shoaling species, they do like the security of a good size group, the bigger the group, the better. With discus, the sex of the group does not seem to matter, what does matter is personality. Every discus has its own personality just as we humans do, and a clash between two individuals is something to sometimes expect when keeping these fish.

Breeding Procedures

Q: My discus finally hatched a batch of eggs and I got some free swimmers. I only have about five left from what I can see, but this is there first batch, so I wasn’t expecting large numbers. The strange thing is, I was always under the impression that once they had free swimming young they would just take care of the fry. Well yesterday to my surprise, they had another batch of eggs and are not looking after the free swimming and the eggs. Is this normal?

A: This is very normal. What has happened, for some reason your number of free swimming  are very low. Normally a batch of at least 150 to 250 sometimes even more, is to be expected. Because only five have survived, the parent discus will breed again, because a batch of this number is not worth bringing on. So you will find these five, if they make it, will be kept back and brought up with the next batch of younger brothers and sisters. If, for what ever reason, a second batch doesn’t materialise, they will keep feeding mucus to the free swimming ones and try again with a third batch. In some cases parent discus may well eat any small batches of fry to clear a clean slate and start again from fresh. As usual, mother nature can be harsh, but this is the discus way of survival, and yours sound as if they are good parents and may well bring on batches ok. Seeing baby discus with their parents is a joy to behold. Just make sure you have plenty of brine shrimp eggs ready to hatch out for the hungry discus fry.

Home Alone

Q: I am going out of town for a week. I have one discus fish and he only seems to eat frozen bloodworms. He does not seem to like much of anything else. I am not sure what to do to feed him while I am away. I would get a feeder, but he really does not eat flakes or pellets. He will eat freeze dreid bloodworms, but he rarely goes to the top of the tank. Do you have any suggestions? Also, maybe if you know of something else they like to eat, I would be glad to hear it.

A: This is a question I hear of only too often. The problem is when discus are fed onlt frozen bloodworms, they will not accept any other foods. The reason is, discus just love bloodworm, like humans like a good old full English fry up. The full English fry up is just as good to human health as the the frozen bloodwormis to the discus, and it will not do them much good if they do not eat anything else. Frozen bloodworm fed on own contains very little nutrition, so any discus fed solely on this will suffer health wise at some point. The best and safest way, as I have covered many times, is to feed freeze dried bloodworm, and if it is held between your fingers tight under water and then released, it will sink to where your discus will feed on it. But your dilemma is you are away for a week. If your auto feeder has freeze dried bloodworm in when released by the feeder, the food will float making it incorrectly placed. My advice is that the discus will be fine for a week without food,so I would make sure water quality is good by means of a good water change before departing, and your discus will be fine. When you return, feed only flake food or any other foods discus pellet food, but 100% no frozon bloodworm at alls. Your discus will be hungry and will try eat and eat anything by then. Foods containing garlic would be a perfect choice, discus love garlic and will rarely turn it away unless they are sick. Once they know this is the only food available, they will eat this and should not cause any more concerns. So with going away, you are in a good position to start the change over for feeding.  Also try discus delights, the gourmet discus food hamper for feeding. It has seven different safe foods in, one food for each day of the week. It also has a garlic food in, as well as some other testy treats for your discus.

Dodgy Discus

Q: My discus have been doing well in my tank for about two months. Now all of a sudden, they have been behaving as if they are sick. I see some that look relatively healthy and active. I have six discus intotal in the tank, and the shoal of rummy-nose tetras that look perfectly healthy, and so do the six corydoras catfish. One of my discus is pretty sick, and it has a whitish colour on some parts of its body (which is usually a dark blue/green colour). He is sitting in the corner of the tank and not swimming all that much. I always give two water changes each week, which is about 25% each time (adding up to 50% each week). I have put Methylene blue in thetank, and it is currently working, just so it can help fight off any fungus if there is any. It is sort of a quick cure thing that treats ich, fungus, skin flukes, etc and it has always worked for me so far. I am pretty nervous, and I don’t know what to do. Can’t bear to see them die. Your reply will be 100% appreciated.

A: Your water changes sound fine at 25% being changed twice a week should pose no problem with water quality. One important thing you didn’t say is what your water test kit readings are. Many discus keepers think that because they change so much water on a regular basis, that they don’t need to test their water. For exsample, say your biological filter is not working properly; one would expect to see a high ammonia reading. This itself could cause the white patches you say the discus have. Methlene blue is a good old fashioned way of treating any fish., but this medication comes with cost. It can knock out your filteration, thus causing your ammonia to rise. Ammonia can burn the skin of the fish, or cause skin flukes which fits in with your description. .My plan of attach here would be. First, do a full water test and see what all your water parimeters are. If any of them are out, address them immediately. Second, use a more filter friendly medication such as wormer plus etc which will treat the skin problem, without knocking your filter system out.

Changing Over To Discus

Q: Soon my 100 gallon 5ft tank will be empty and I would like to start again and do a discus tank. The tank will be filtered by a Eheim 2180 and 2078 so will be well over filtered – also the 2180 has a UVC. I have a few questions though before I take the plunge:

  • Can I keep them in tap water or will I have to use reverse osmsis water?
  • How many discus should I keep in this size tank?
  • I was also thinking about putting my two angel fish in with them. I have seen this done, but I’m sure I read somewhere that it’s not recommended? Will this be ok?

A: A five foot tank is fine for keeping discus in, and you will be able to keep ten fully grown discus in a tank of this size. You could if you wanted to, add a shoal of tetras, corydoras catfish and L plecs numbers. Keeping  angels with discus has always been a grey area, so I will just comment on my own experiences of the last 35 years or so of fish keeping. I have kept angels with discus with no problems at all. They live together in the same way as discus do. What I mean is they will sort out a pecking order when new ones arrive between them selves and settle in great, just the same way as adding just discus.  After all, they do live together in the wild, and they are both cichlids. That said I do have a little secret that may be why some people do get problems, and I, and others have not. Angels carry intestinal worms which will not bother them and they are also a lot more tolerant to desease than discus. Mixed with discus, which don’t tolerate worms so well as it has been commonly documented of late, and you may get problems. So my advice is, if you do mix angels with discus make sure you regularly worm them once a month and any parasites will be kept down to safe levels. As to your water, it depends on if you live in a soft water area or not. If you live in an area and your water is below a GH of 10 (soft water), ordinary tap water treated with an water safe treatment will be fine, or better still use an HMA unit which will take out any harmful contaminants in the water before adding it to your tank. If you live in an area which is deemed as hard water (above a GH of 10), you will need to use an reverse osmotic unit to soften the water first before filling your tank. If you still decide to go ahead, welcome to the wonderful world of discus keeping. They really are the king of the aquarium.

Shy And Nervous Discus

Q: I bought four discus about a month ago and they are housed in my 75-gallon tank. I have been planning to add a larger shoal of them soon. I am pleased they have settled well and seem to get along great; however this is only when nobody is in the room. I know that discus are shy and get scared easily at first, but it has already been a month, and I can’t seem to figure out why thet are so afraid of me. They know that I am the only person who feeds them, cleans their tank. But they still run to the back of the tank when I stand up or walk in the room.  They should be able to realise I am harmless because they see the shoal of seven rummy nose tetras constantly swimming back and forth at the front of the glass when I come near them. I give them a 25-percent water change twice a week, their temperature is about 82f. Their water quality is good because they have bright colouration, and are not black. Also the rummy nose tetras have bright , colourful noses (their noses are not pale or orangey tint) . I still can’t figure out what is wrong. They should feel safe, since my tank is very well planted, with both live and plastic plants (soon to be mostly live plants). They know that they have many places to hide if they feel nervous. So what could be wrong? I just want my discus to feel safe and happy. I absolutely love seeing videos online where the discus go and eat like crazy out of the owners hand!

A: Your tank size sounds fine, and is ok for discus with the water changes you are doing. Your temperature should be a little higher at 86f (30c) or you run the risk of having parasites, which could be what is bothering your discus. But the biggest thing to remember with discus is that they are a shoaling species and like to be in groups of at least six or more to feel secure. You still have some room to increase the size of the group to seven or eight – if you do this I would expect your discus to settle better and not be so nervous. Also it would be a good idea to test all water parameters, just in case any other readings could be out.

Starting Out With Discus

Q: I’d have to say it’s been a good few years since I last had my 77 gallon aquarium stocked. Throwing a shoal of neon’s with a bunch of plastic plants would not keep my attention for long.  Some unique speicies, a live plant set up, and a theme would make things more interesting. One fish I have always wanted to keep was discus, but a few generic stores round here don’t keep them. So, if I plan on going all out now, what better theme to choice than Amazon river scene. Now to my question: what do I need to do now? I’ve heard that discus are not easy to keep, needing a well balanced diet, and temperatures of 80f upwards. Are their any variations between breeds? With so many types for sale, what is out there? What things need to be considered?

A: A 77 gallon tank would be perfect for discus, and would house around seven fully grown, plus some room for a few other Amazon species to keep you interested. If you want a themed tank, make it an Amazon tank with sword plants, bog wood, and branch wood to make it look like a river scene. For tank mates, you could add cardinals, corydora cat fish, L plecs, harlequins, and even some dwarf cichlids. Natural gravel or river sand is the best substrate for the bottom, and temperature should be set at 86f (30c). When the tank is running properly, it is best to add the tank mates first. This will mature the tank filters ready for the discus  to be added after around 6-8 weeks if Ammonia levels have settled. It would be best in a new tank at this stage to add seven young small discus and let them grow on. Two reasons for this, the price tag will be lower, and because they are small, the load of the filter will be less than over loading it with seven fully grown one’s. If you were to buy a few discus first, and then add some more later, you may get problems with the discus already in residence accepting the new discus. So best if possible to add any new discus if possible together. If everything is correct, and your water is right, discus are as easy as any other fish to keep. What normally happens is, new keepers set the tank up wrong with a low temperature, water too hard, or PH too high and blame the discus when it all goes wrong saying they are hard to keep. Another thing you will hear is ‘feed lots of beef heart’. Beef heart is not part of  a discus natural diet in the wild, but a small amount will help them with protein. I have never understood why people are hell bent on filling discus up with herds of cows. Too much every day can cause problems, as their digestive system cannot take it over a long period. Instead offer it to them once or twice a week, and feed pellet foods, good quality flake foods and granular foods. A box of discus delights gourmet hamper foods will give them everything they need all in one hamper box. Or tetra foods are just as good a quality. Good luck, and happy discus keeping.

What Happened?

Q: The reading in my discus tank has always been zero, but I tested it last night and Ammonia is between 0.25 and 0.50! No sign of Nitrite. Also my PH has been dropping, it was 6.4 for ages now it’s dropped below six. I can’t see any dead fish, a few plants look a bit funny but nothing to out of the ordinary. Any ideas what’s causing it? I’m going to do a 50% water change to bring it down to 0.

A: If the reading in your tank has been zero something must have knocked out your biological filter. You have asked ‘any ideas what is causing it?’ First up is have you been using any medications in the tank? If you have, the chemicals may have killed off the good bacteria in your filter system, which would cause ammonia to rise. Another idea could be over stocking, which would put a strain on the filter, or sometimes keepers clean out the filter too much washing out the beneficial bacteria that has built up to break down the ammonia. Over feeding is another option that may have also caused this issue. If all was well before, it must be one of these issues that has made the difference, and must be addressed as soon as possible otherwise your discus will not stay in good health for long. A good tip would be to use some ammo lock to lock up the ammonia. You will still see a reading of ammonia, but it will stop the ammonia burning the gills of the discus.

Baby Discus Removal

Q: When is the best time to remove my two week old baby discus fry from the adults? They are currently about the size of a 20p piece and the female is looking very tired.

A: It is possible to remove the fry from discus parents just three days after free swimming. Many UK breeders tend to keep fry with the parents for much longer (up to a month) before taking them away. If your fry are up to the 20p size and the female is tiring, I would recommend removing them now. Remember to treat for flukes at this age. This is one of the things that will kill many of the discus fry when around four weeks old. It is commonly known as the four week syndrome. Once the discus are  over 2” long they can be treated the same as the bigger discus from then on.

Discus Water Change

Q: One of my discus wasn’t looking too happy so I decided to do a 70% water change (the second water change that day) on the first change I rinsed my internal filter sponges in the water I removed from the tank. However, after doing the second change two of the discus shed their mucus coat. All the discus are swimming around happy and eating but is this something to be concerned about?

A: 70% water change is far too much to change at one time, unless you are using Chorine free water such as HMA or RO water, and water that is the same temperature. You say you washed out the filter sponges in tank water. But did you know that by doing this even in tank water you will have washed out 95% of the good bacteria that had colonised in the sponge filter. Ammonia will then rise which could be why your discus shed mucus. You did not say if you tested the water. My bet is that the ammonia level has gone up. Try doing 25% water changes just once at any time, or better still 25% twice a week spaced out. I never recommend any more than this unless you have a discus health problem. With the sponges, just gently squash them out to free them up. Never wash them out completely.

Changing From Marine To Discus

Q: I have just shut down my reef tank, and have the 240-litre, four foot tank empty. My wife has asked for larger fish, and I would like a showpiece tank with plenty of plants. This has been in the planning stages for weeks, and I have bought an Eheim professional external, hydor external heater, and a pressurised CO2 set up. The tank has four 39w T5 tubes, which will need replacing as they are marine tubes. How many discus can I keep in this tank? I know I need some dither fish, but I’m not keen on cardinals as everyone seems to lose them. I will be planning on carrying out two 20% water changes per week. Should I use RO water, or will normal tap water suffice? I am in Devon and our water is pretty soft.

A: Your tank would be okay to keep six discus in. Four tubes may be too bright for discus, unless you have plenty of floating plants for cover. Original tropical light tubes will be fine to replace your marine tubes. Your filteration and heating sound okay, as with the CO2 set up for the plants. You will need to step up the water changes to 25%. As you are down here in sunny Devon the same as myself, you should be able to get away with using just an HMA unit as I do. It is possible to use Devon tap water, but if you do, make sure you add some tap safe or similar to treat your water before adding it to your tank. I have always found cardinal to be fine, but it depends on where they come from. However, you can add red lined torpedo barbs which are stunning, and get on great with discus even though they come from Idia. But make sure you have plenty of aeration in the tank, and the temperature is not above 86f (30c) if you do keep red lines with discus.

Discus Interest

Q: I have  been interested in discus for some time now, the only issue is I have to get over the prices of them. I have an 55 gallon tank and probably consider it lightly planted. I currently have two Siamese algae eaters, one pleco, one red tailed shark and two Albino angels. I was wondering if I would be able to mix discus with these fish? I figure with the angel fish might be okay due to them being in the same family, and I’m also not too worried about the red tailed shark because he hides a lot from the angel fish. I would appreciate your help and what kind you recommend?

A: Discus can be expensive, and the best way to get them at a low price is to buy young small fish, and grow them on. The bigger the discus, usally the bigger the price tag. The Siamese algae eaters should be okay with discus. Angels can be hit and miss with discus, and some discus keepers prefer not to keep them together. I have kept them together in the past with no problems. It all depends on the personality of the fish, just the same as us humans. The best thing to do, is to change around the territory on the day you add the new discus with your existing fish. This way they should all settle together with all the territory altered. The red tailed shark will have to be rehomed if you go ahead, or moved to a second tank. He may well hind during the day, but at night he will come out and worry the discus. Apart from different water conditions to discus, they do not normally live together peacefully. Apart from that, your tank sounds fine for keeping discus.

How Many Discus Can I Keep?

Q: I have been keeping fish for around eight months and have loved every minute of it. I have learned a bit from a few mistakes and have had many different types of tropical fish so far, but I want to try out discus. The problem I have is that I think my tank may be too small, but I wanted a second opinion. My set-up is as follows. Juwel Lido 120 (planted and bogwood currently with a bit of slate but this will be removed) Internal bio filter. External Aqua One Aquis 1250. Iwas told 8 –10 gallons for each fully grown discus, but since my tank is approximately 26 gallons that leaves room for about three discus, is this correct?

A: You are correct your tank is too small for a normal size shoal of discus, if you go with the standard rules. But not impossible to keep some in! At times the anarchist side of me comes out and I say rules are made to be broken. Ten gallons for each discus is correct, so you would not be able to keep the magic number of six discus in a tank of this size. I say magic number, because discus are a shoaling fish and would need the security of at least six members in the group to do best. But sometimes rules can be broken, with a little understanding and planning. If this is the biggest tank you can afford, it MAY be possible to house say three, two and a half inch – 4 inch discus as long as you have some other dither fish in with them to make them feel secure. This is not ideal, but it has worked before and the discus were happy. These can be either a small group of neons or cardinals, six coryadora catfish, or say two golden nuggets. I would not recommend, or push it more than that, and you would need to do a 25% water change every week, or better still twice every week.

The Early Bird Catches the Worm

Q: I have heard and have read lots of comments on worming discus. I have never wormed my discus before and don’t know how to do it. Two of my fish have gone emaciated and very thin particularly above the eyes. Do you think my discus has worms and what is the best way of controlling them if they have?

A: Many people do not realise that discus need worming and many have never wormed them. Some never get problems and some do, although now and again the hobbyist that has never wormed their fish say ‘I can’t understand why my discus has died’ although they admit they have gone very thin and emaciated even though the fish were feeding very well. I worm my discus every month or when ever I get new ones in and believe prevention is better than cure. Once worms take a hold of a discus it can be very hard, if at all to get the fish back to full health. Worms are a fact of life for discus and every discus carries it own army of worms. Normally these worms are not a problem, but if a fish is bullied or stressed its natural immunity system is pulled down and compromised and worms can take a hold. My guess is by the description of your discus, its sounds like your fish may possibly have Helminthic internal parasites or tape worms. If you have never wormed these fish before, you may well be surprised by the results. Worming discus can be done in many ways, some use dog wormers which I would not recommend. Dog worming products are normally administered by a vet according to the weight of the animal. There is a big difference in the weight of an Alsatian and a discus, and it has happened in some cases where a tank full of discus, has been lost through using incorrect treatments. If using alternative wormers not meant for approved aquatic use from a vet, they are a different strength to the aquatic wormers, using a bigger dosage is self-defeating as the parasites can quickly build up a resistance to these types of wormers. Particularly those sold for cattle and pig use, which aren’t water-soluble. Bottom line, don’t economise and use something that won’t work long term.
This is not scare mongering, this is one of the reasons behind the new regulations currently in force, they are there to stop the unregulated use of chemicals on the wrong animals, not to help manufacturers of licensed products to get rich. Too many people with a little knowledge think they can cheat the system, and that small amount of knowledge can be very dangerous. This has often led to parasites building up immunity to a product, or the untimely death of your pet. Any person selling or buying a product for one animal and then dispensing it for another, can be subject to very heavy fines, the rules are there to protect you and your pets, and there may be long term damage to your stock if you use cat, dog, cattle or pig wormers for aquatic use. The wormer I use is wormer plus (flubenel 15) a soluble powder type that has a wide spectrum usage, manufactured for discus use and can control more than just worms. It works out to about 50p per week for a 50-gallon tank, so worming your fish need not be expensive and could save a lot of heartache in the long run. With the correct, recommended, licensed products avable, is it worth taking the risk?

Good Mates

Q:I am setting up a tank for keeping discus. What tank mates can I keep with them?

A:When selecting other species of fish to keep with discus, it is not just a case of adding fish that will live in the same water as discus. Obviously they will need to take a high tempiturture, but also water that is  soft and acidic. Piranhas hail from the same area as discus, but are totally unsuitable to live together in the home aquarium. This is because they appear on the piranha’s food menu along with angels and many other species. Tetras are fine with discus, as long as they are added when the discus are under the 4” size. Some discus over this size may eat small tetras. Corydorus cat fish, small L pecs, dwarf cichlids and angels, with the latter being a grey area with some discus keepers. Some believe the angels will pass on disease to the discus, which is why some do not mix the two together. For many years I have mixed discus and angels together with no problems what so ever, but then I treat and worm my fish on a regular basis and this may be the answer to the success.

Where To Go?


Q:Discus keeping seems to be on the up. I have kept nearly every fish apart from them. Where is the best place to find information on them and any good clubs or books etc you can recommend joining  or reading?

A:If you can get online, many discus clubs and forums can be found. All dedicated to discus keepers in the UK. Many hobbyist, breeders and traders are members and will help any other members with help, advice or just a friendly bit of banter, and most search engines will find them if you just type in  DISCUS FISH FORUMS. Also in some areas but not all, you may find some local good clubs. A good book to start off with is ‘’discus…as a hobby’’ by Jim E. Quarles. It is easy to understand, short and sweet and straight to the point. It also covers everything from feeding to breeding. Andrew Soh’s book Discus…..the naked truth is well worth a read, or the one you are reading now is the most updated book. I will be covering all the points that have surrounded this fish and letting all the ‘secrets’ out of the bag. I can’t see any point in shrouding the hobby in mystery, if everybody can get the best from their fish. The fish will benefit and the hobbyist will enjoy the hobby better, everybody wins. Hopefully I will meet you on one of the forums, good luck.

Aggresive Pair

Q: I bought six small discus about a year ago. Since then they have grown on, two of them have paired off and will not let any of the others anywhere near a sword plant on the left hand side of the tank. They have now laid eggs on a leaf and are acting very aggressive to anything that comes near the spawning site. How if at all can I raise the babies if they hatch?

A: Ideally in this case if possible, move all the other fish out of the tank just leaving the eggs and the parents in the tank. They should then look after the eggs and raise the young by them selves. Do not feed the fry for the first week, but add newly hatched brine shrimp which is the best first food to feed discus fry after they have been free swimming for a week. If you don’t want or have not the time for hatching shrimp eggs. Many preparatory man made foods are available, such as discus delights baby food mix, tetra baby food for egg layers or ZM foods for fry are all good foods for discus fry. If you want to breed from this pair on a regular basis, it would be a good idea to set up a twenty gallon breeding tank for this task.

Spotty Discus

Q: My discus have a very fine white dusting over them looking like a film of white powder. I have looked in the aquatic fish disease books and it looks like they may have velvet. I have not added any new discus or any other fish in the aquarium. So how has this disease entered into my tank?

A: If you have not introduced any new stock to your tank and all cleaning buckets, pipes and nets are only kept  for this one tank then there is only one answer, ammonia. In all the years I have kept discus the only way in this case that could have caused velvet is a high level of ammonia must have been exposed to your discus. Many times I have heard keepers say they change the water twice  a week so I don’t need to test my tank water for ammonia. Only to find the biological filtration system is not working properly. Another common mistake is too many large water changes every day. What happens here is the beneficial bacteria in the filter just does not gets chance to build itself up in large enough numbers . Consequently ammonia will build up and the filter can’t cope with the load, the discus get stressed and ammonia burnt, and the secondary problem then is a break out of velvet.

Unwanted Discus

Q: A friend of mine has closed his tank and given me a small two-inch discus. I have put him/her in my community tank for now and it seems to be doing okay although it’s only been 24-hours. My issue is that my water is about pH 8.0 and quite hard, I don’t think my friend had the discus for long. He bought it from a local fish shop and his water is similar to mine. I’ve always wanted these fish, but have been put off from all the rumours about keeping them. Will the fish be okay or will it die in my water?  I acclimatised the discus over about two and a half hours and it has settled okay. It’s kept with two large angels, three Polka dot loach, three platys, two sae and a Spotted Climbing perch. I know they do better in groups but don’t want to buy anymore if they won’t survive! The tank is a four-foot 240-litre, planted with two externals running. Also the tank is at 26C and I know they like warmer water. It doesn’t sound good, but will it survive and should I buy a couple more? Hope you can help? Thanks.

A: First of all, don’t be put off by rumours about keeping these fish. Normally it is keepers who don’t understand their requirements and then blame the discus as difficult fish to keep. With the correct conditions and understanding, discus are not difficult fish to keep at all. First of all you say your PH is at 8.0 which if you go by old books is high for discus, which should really be kept at around 6.5 – 7.0 ideally. But they can be kept in PH this high, and if fact in the Far East they raise the PH as high as 8.2 to devolved the bones and skeleton of the fish when growing. So if these discus are tank bred, it should be possible and they should survive in your PH. But if they are wild discus, they may well struggle because they would have been used to a much lower PH value in the wild. You say your hardness is quite hard, but say what the readings are. Again the same as the PH discus can live in harder water, but softer water is preferred to do their best, ideally below 10GH. Your temperature is too low for keeping discus, and will need to be raised up to 86f/30c. Discus being a shoaling species would be better in a group of at least six or more, which your tank would be okay with six, plus the other fish you have that would be okay to stay. Discus can be kept with angels, but you say yours are large. So success here depends on if your angel pick on the discus, of leave them alone. If they don’t bother them too much, they should be okay. Just make sure you worm the tank every month to stop any cross infection of internal parasites, which is why you will read in some places why discus and angels cannot be mixed. They can if precautions are taken.  The polka dot loaches are lovely looking fish and will be fine in discus water and are fine with discus when small. But some can get to 5″ -6″ when fully grown and this is when they could upset the discus. You may be lucky and yours may be peaceful, but some can ‘fly’ around the tank very fast which the discus will not appreciate. The two sae are fine, but the platys may not fair well in the higher temperatures. Forget the perch, he will not be a good tank mate for any discus for many reasons. If you go ahead with the discus, the pearch will need to be re-homed.