Discus Fish – Step by Step Starting a Discus Tank

Raising baby discus can be a challenge. The person just starting to raise them may make mistakes that could have been avoided by following some simple rules.

This article, based on my experience, will provide some guidelines that may help the hobbyist get started on the right foot (or fin). The keys to raising healthy discus are good stock and the proper environment.

Where to Buy Discus Fish?

Discus can be obtained from a pet store, a local breeder, or by online order. If you are not sure where to get good babies, ask people who have discus. Find out where they purchased their fish and if they are satisfied.

Be especially careful of buying discus thru online order, because you have to depend on the seller to send you healthy fish and the proper strain.

How to Choose Good Discus Fish?

Healthy Discus Fish

It is best if you can look at the discus before buying them. Here is what to look for. First of all, the discus should be swimming. Seriously though, discus can tell us when they are not feeling good by the way they act.

A change in color or heavy breathing may indicate a sick fish or poor water conditions. The discus should be active and looking for food. Avoid fish that are dark in color, have clamped fins, or that are hiding. Ask to see the fish being fed, so you can be sure they are eating.

The Shape, Size, and Color of Discus Fish

Once you have spotted healthy fish, take a closer look. Look at their shape, size, and color. Select discus with nice round body shape. Avoid fish with an elongated or oval shape. Check for fin extension. Avoid discus with an undercut or deformed fins.

Look at the head straight on. A skinny head could be a sign of stress caused by malnutrition, disease, or poor tank conditions. Make sure the body and forehead are in a straight line.

Check the mouth for deformities. The mouth should be straight, not pushed to either side. Compare the size of the eyes to the body. Eyes that seem to be unusually large may indicate stunted fish.

Discus Fish Gills

Finally, look at the gills. Make sure the gill plates fully cover the gill area. Check the breathing. Heavy breathing on either side may indicate poor water quality, gill or body flukes, or overeating. Low pH, a lack of oxygen, the build-up of nitrites or ammonia may cause heavy breathing. These conditions can often be corrected by changing water.

High temperatures may cause heavy breathing, too. Scratching against objects or twitching may indicate gill or body flukes. If you purchase a discus with flukes, it can be treated in a hospital tank. Overeating can also cause heavy breathing. If this is the case, breathing will return to normal after the food is digested.

Food for Discus Fish

After looking at the discus over carefully, ask questions! Try to obtain as much information about the fish as possible. Find out what type of food the discus eat. Then you can feed them the same food and switch them over to your own food gradually.

Be wary of fish that are fed freshwater foods. Black worms and glass worms may carry gill flukes. Try to find out the fish’s age. This can be a rough indicator of stunted fish.

A general guideline to discus size is: at two months, the discus should be between the size of a quarter and a half dollar; at three months, the discus should be roughly the size of a silver dollar. These sizes do not include the fins and are general guidelines because the growth rate of discus can vary, depending on the sex and strain of the discus.

Colors of Discus Fish

Judging the color of young discus may be difficult. Some of the more colorful strains, such as turquoise, may start developing color at 8-12 weeks. Less colorful strains may not start developing color until 8-10 months. Discus usually reach their full color at sexual maturity, about 9-14 months.

Be cautious of discus imported from the Far East, because many of them have been treated with color enhancing hormones. Discus treated with these hormones will be colorful as babies, but the color will fade as the discus grow and the hormones wear off.

Some indicators of hormone-treated fish are extremely vivid colors in the babies. Hormone treated fish may also show an orangish background. While all discus may show some aggressiveness towards each other, hormone-treated discus have a tendency to be more aggressive at an earlier age.

The key to successfully raising discus starts with healthy stock. This involves finding a reputable breeder or pet store, picking fish that look healthy, and asking as many questions as possible. While this may seem like a lot of work, and the number of things to remember overwhelming, with practice it becomes second nature. The results are large, healthy discus.

Discus Fish Tank Setup

Before purchasing your discus, you must have the aquarium set up and ready for the discus. The following list is the equipment I have found useful for starting with 6-12 discus that are quarter size.

1. A 10-20 gallon tank, with a hood and light. Do not start out with a larger tank, as the babies have a tendency to get disoriented in them. If you have more discus, allow approximately one gallon of water per baby.

2. Two sponge filters. I prefer using the uxcell XINYOU XY-380, the AQUANEAT Double Bio Sponge Filter, or homemade sponge filters.

3. An outside filter. The Whisper IQ works well.

4. A high-quality heater and thermometer. Avoid cheap heaters, because the contact points can stick and boil your fish.

5. An air pump with enough power to run at least four outlets.

6. A siphon hose or hydro-clean for easy water changes and to vacuum the bottom of the tank with.

7. Aquarium test kits to test the water for pH, nitrites, ammonia, and chlorine.

8. A bacteria culture to start bacteria growth in the aquarium. Fritz-zyne #7 or water from the sponge filter of the tank your discus came from will work.

This aquarium set up uses a bare tank because it is much easier to keep clean. If you want some scenery in the tank, you can set some potted plants in the tank. If you really want to have gravel in your tank, be sure to use an under gravel filter, with about one inch of gravel. This will be fairly easy to hydro-clean.

Make sure the under gravel filter has 3/4″ to 1″ lift tubes for the best aeration. I prefer to use a bare tank with a sponge filter, rather than a tank with gravel because it is easier to maintain.

With a sponge filter, less of the uneaten food is absorbed into the filter medium. A sponge filter allows more surface area for absorption, this is more efficient. It is also easier to medicate fish in a bare tank.

After you decide how to set up your tank, choose a location. Discus seem to prefer an area with little traffic. They do not like to be close to the floor, either.

When your tank is in place, fill it with water and start the filters running. Test your water for chlorine and chloramine. If you have either, use a neutralizer to get rid of it. Put the heater in and set the temperature in the range of 80 – 84 degrees. After forty-eight hours check the pH. It should be in the range of 6.5 to 7.5. If it is outside of this, use pH up or pH down.

Next, you need to add a bacteria culture to the tank (a commercial preparation or sponge filter squeezings). After adding the bacteria culture, let the tank set for 3-7 days. During that time check the water conditions. The pH should be in the 6.5 to 7.5 range. There should be no nitrites, ammonia, or chlorine. When the water is ready, you can add your discus.

When you get your discus, do not feed them for the first 24 hours. If the fish seem active and hungry after this time, start feeding them lightly. Remove any uneaten food after one hour. Check the water conditions daily. If they go out of the given ranges, do a 1/3 water change. If some of the discus are eating and some are not, put the ones that are not eating in a separate tank and medicate.

If, during the 24 hours, the fish show signs of stress, do not panic. Some signs of stress are clamped fins, shaking, scratching, shimmying, heavy breathing, and a dark or black color. If this happens, first check your water conditions. Poor water can cause stress. If the water is ok, try upping the temperature to 90 degrees for 24 hours. The higher temperature may cause heavy breathing, but may help the discus get better. If the discus do not do better after 48 hours, you should contact the seller for further ideas on how to treat them. The seller should be familiar with the discus and have some experience in treating sick fish.

In a few weeks, if no medication was needed, the environment of the tank will stabilize. You may notice the pH dropping into the acid range. This is normal. It just means the biological filter is working to break down waste products. You should now do small water changes, about 1/3 of the tank per week. This will bring up the pH. Even if there is no pH change, go ahead and do a small water change, just to clean the bottom of the tank.

After 3-4 months, the sponge filters will be well established with bacteria. This is when you will want to start cleaning them. Do not clean both sponges at one time, this upsets the biological filter too much. It is best to clean one sponge one week and the other sponge the next week. To clean a sponge filter, use water from the aquarium. Do not use tap water or you may kill the bacteria. Put some water in a container and immerse the sponge filter in it. Squeeze out the excess water. Do this several times to remove the waste products.

Now your tank is looking good and the discus are healthy and active. Keep it that way! Do not add fish or plants without quarantining them first. Adding new fish or plants directly to your tank is asking for trouble. Discus should not be kept with other types of fish, except for a few scavengers. If you want scavengers, the best ones to get are Royal Farlowellas or Botia loaches. Both of these fish get along with discus and can tolerate the higher temperatures that discus like. It is not a good idea to mix discus and angelfish. They are too aggressive to be kept together.

Part of raising healthy discus is a proper diet. A variety of foods is essential. I usually feed my babies ground up beef heart, carnivore flake food, live brine shrimp, and frozen brine shrimp. When the babies are large enough to handle it, I feed them frozen bloodworms, freeze-dried tubifex worms, frozen ocean plankton, and pellet food (if they will take it).