An introduction to Discus: Part I


Superstar Fish
Oct 22, 2002
Cincinnati, Ohio
An introduction to Discus

“King of the aquarium”
Part I: An introduction to discus

Discus really are amazing fish. In my opinion they are one of the most fascinating genus’ in cichlids, which is saying a lot since Cichlids are all really breathtaking fish with each their own special traits. In this article I will try to inform you about discus themselves, their care, and history. Hopefully I will also convince you to try discus out for yourself, so you can be as addicted to them as I am.

Discus History
Discus fish are named for their disc shape and similarity to the discus one would throw in a track and field game, and are cichlids, in the Symphysodon genus. The first actual discus described was Symphysodon discus heckel, by Dr. Heckel in 1840 which was discovered at one of the Rio Negro tributaries. It was first introduced into the hobby in 1921 at Hamburg, West Germany. This fish has 3 of the 9 vertical bars darker; one through the head, middle, and tail and blue striations on its sides.

The second was Symphysodon aequifasciata aequifasciata, which is also known as the Green discus, and was described in 1904 by Pellegrin and formally introduced into the hobby in 1921. They are native to Lake Tefe and Peru. During the 1930’s they received quite a bit of attention, as they were the first of the genus to have their spawning observed. Eventually in the 1950’s they were successfully spawned by Schmidt-Focke and Jack Wattley.

By the year 1960, Schultz had described two new sub species of Symphysodon aequifasciata; S. aequifasciata axelrodi (Brown Discus) and S. aequifasciata haraldi (Blue discus.)

Now during more modern times, discus have evolved into spectacularly colorful and bright fish from many years of selective breeding. Many new strains come up into the hobby varying from Pigeon bloods to Turquoise to magnificent Blues. It is simply amazing how much color these fish have!

General Keeping
Depending on what you want, there are two ways you can go with keeping discus. One way would be bare bottom, which is in my opinion the best way to grow out and keep discus. The tank itself is bare, with no substrate, as with substrate, debri and waste is missed, which degrades your water quality, and since discus need clean water to grow, it will detract from the discus’ health. With bare bottom waste can be easily spotted and siphoned up; however with a traditional planted tank, waste is often missed and often plants will not fair well with the large water changes discus require. The other way would be a traditional planted tank as I have mentioned above, is really not the best environment for these fish. I would only recommend keeping adult fish that have stopped growing in a planted tank, as they do not need the heavy feedings or water changes that young or semi adult fish do.

Often people do “hybrid” tanks, or tanks with a bare bottom but with potted plants or mounted driftwood in the tank. This is perfectly fine, and in my experience works well, however you will want to pick hardy plants like anubias, java fern, swords, and Vals.

Tank Size
A general rule is 10 gallons per discus, however this does not mean that you can go out and buy a discus then stick it into a 10 gallon aquarium. These fish need to be in groups of 6 or more, so at least a 55 gallon is required. Breeding pairs can also be kept in 29 gallons or more.

A good heater is needed, I would suggest two actually because if one goes out, you have the other as a fail safe as the water temperature will not fall as fast, which gives you time to see the problem and stop it. These fish like it hot, and temperature changes can often result in health problems, so a good quality heater that will not burn out on you and can put out enough heat is necessary. Good filtration is also a necessity. I suggest a HOB (Hang on back filter) such as an Aqua clear, and a GPH (gallon per hour) rating of ten times the tank volume.

These fish require a tad bit higher of a temperature than other fish. Usually a temperature of around 85 degrees F will be fine; however any temperature lower than 80 degrees F will often make discus very susceptible to ich.

Water Parameters
Contrary to the common belief, discus do not need a ph around 6.5 and soft water. My fish are currently in Cincinnati tap which has a Ph of 8.5 and hardness off the chart! Remember it is way more important to keep the parameters constant rather than try to pinpoint a certain level. Actually young fish are often benefited by mineral rich water, as without those minerals, the may not grow properly. Only breeding pairs need a lower Ph, soft water, and low conductivity. Conductivity is defined as the total dissolved salts, or ions in water. So in other words it means how much salt or other solutions you have in your water. Anyway if you have a high hardness the egg shells will harden, which will make the shells impassable and not allow oxygen to get to the eggs, which is necessary element for fry development, causing them to not hatch.

Water Changes
Young fish really do need large water changes. On my younger fish I do at least a 50% daily water change. I recommend doing at least a 30% water changes at least every day for young fish. Older fish will be quite content with just 30% daily water changes. However, because of different stocking levels and tank sizes, different water change amounts are required. You really just want to keep your nitrates at 0, so how many waterchanges you may need to do to keep your nitrates low, all depends on the different conditions in your individual tank. Also remember while you’re doing water changes make sure to siphon up any waste you see, and scrub down the sides of the tank, as often waste in the form of slime will appear on the glass. A general rule is to wipe down the insides of the tank at least every other day or so.

Discus do need a varied diet with high protein foods and many daily feedings (the latter in general applies to mostly younger fish). A good diet would consist of many different types of frozen foods and live foods (for example: blood worms, Brine shrimp, Jack Wattley discus formula, Black worms, and beef heart) and also many types of dry foods (Ex. tetra bits, Spectrum discus formula). Beef heart is very messy though in my opinion, so I tend to feed only lightly with it. Personally I like bloodworms as a staple and every so once and a while i feed black worms. Young fish need many daily feedings, usually 4-6 times works out well, to grow quickly and properly.

Choosing discus
When looking for discus, look for fish that appear in general healthy. Do not choose fish that are dark, shy away from the tank, or have obvious genetic faults. Pick fish that have a good round shape, not football, red eyes, and good eye vs. body size proportion. A fish with a small body and big eyes often is stunted and should therefore be avoided. I would not recommend buying fish from a pet store, as often pet store discus are in poor health and not the highest of quality. However I have also seen many that have nice discus, but in general most sell poor quality and sick discus. Instead of buying from a store, buy from a well known breeder. Local breeders are a perfect source. If you are unable to find a local breeder or hobbyist, ordering fish online is a good substitution. Ordering fish online may seem risky, though if you order from a well established and good breeder, you will receive fish that are ten times better than the average pet store discus.

People jump into discus sometimes, and in reality these are expensive fish. So please do not be one of those people that go into discus without reading and throw a lot of money around, only to find that often your hard earned cash will go to waste. So please read, read, read before jumping into discus. Ask questions and read all you can on online message boards such as, and Believe me those people will be your best friends when it comes to taking the plunge into discus.

Final note
Just in reiteration of what I said in the beginning, I hope that I have helped everyone in their discus quest, or maybe even convince you into trying them. They really are amazing fish, and I hope you all get to experience the wonderful joy that I get from them for yourself. But just one last note, discus really are not that difficult as everyone perceives them to be, all they really need is a lot of time and TLC. If I can keep them… anybody can!

Works Cited (forums) (forums) (forums)

Back to Nature Guide to Discus
By: Dick Au
Copyright © 1998
Fohrman Aquaristik AB

Degen Discus
By: Bernd Degen
Copyright © 1996
TFH Publications Inc.

Baensch Aquarium Atlas Volume 1
By: Hans A. Baensch
Copyright © 1982/1986/1991/1996/1997

If anyone has any questions or comments you can PM me or send me an email at and I will try answer any questions you may have.

Next article in this series, Part II: Breeding discus: Not all its cracked up to be!

Any comments/suggestions?



Last edited:
Jul 9, 2003
Columbia, SC

2 thumbs up!

Great intro to discus. I know i refer to some message boards a good bit just to make sure i am doing it right.......but i think i now know where to find it all in one place ;)

Really, thats all you gotta learn/know to start with discus...:D And to think people blow it out of the water *crazysmil *crazysmil

Well great article! Do i hear a sticky!?!?


Elite Fish
Oct 22, 2002
Some cories work, some don't. L number plecs, some dwarfs, for the bigger tank stingrays and uaru make impressive tankmates.
Note that research into discus dna indicates that all discus are one species and that the different 'subspecies', heckels and so on are just colour variations.

Oct 23, 2004
queensbury ny
Visit site
i have been a fish owner for about17yrs,but this is my first time owning discus.we got 2 candy apple red turquoise yesturday at first one hid and now w/ some plants,a holey stone and a clown pleco we think we want one more cause now they r fine. i would love a blue diamond.

Jul 9, 2003
Columbia, SC
Welcome Jabber, happen to have any pics of the tank or fish? We all love to see discus pics ;)

Yes teenie weeni fish, medium fish, etc...are ranks. They rise with a certain amount of posts. Its no status symbol though. Look at my post count and then at fishboy's.....i'm older and have more posts, he is younger with less.....but he is so much smarter than me :) ;)