Hi Mack, this is a caresheet my finace and I wrote up some time ago, thought I would go ahead and post it incase it could be of some use to you.
Angela
Basic Requirements and Care For maintaining Discus Fish (Symphysodon heckeli, & Symphysodn discus)
Basic Aquarium Set-Up
When first purchasing discus you have to consider tank size, you will want to have approximately 15gallons or more per fish. For example, a suitable sized tank for four adult Discus would be a 75gallon tank. In your tank it is best to keep exclusively Discus, but if you want to add other species, make sure that they are not fish that will pick on your Discus, or be too boisterous as to stress your Discus, two good choices are Angelfish and German Rams.
Another very crucial consideration when thinking about Discus is filtration, these fish are highly intolerable of poor water conditions, so filtration is a major factor in their care. A good way to go with filtration for your Discus aquarium is to hook up a high output external cannister filter with a good biolgical filter media inside, along with the external cannister you can also use one or more 'PowerHeads' which you can outfit with a sponge pre-filter for the purpose of removing any additional free floating particles. In addition to stong filtration, frequent water changes are essential to keep your Discus thriving, I usually recommend approximately 20-25% at least twice weekly.
The last major thing to look at when setting up your tank is how to decorate or 'AquaScape' the artificial environment that you are setting up. A very common direction to go when setting up a Discus aquarium is to go the route of a planted aquarium, this will help in keeping a healthy environment for your fish, as well as giving them a retreat if they get startled or just feel that they need to hide. Along with the plants you choose, which there are many to choose from, you can also go with driftwood and/or small amounts of rock work to finish off the look of your aquarium, a substrate that works well in this type of set-up is a medium-grain sand such as Silica sand. If you decide to go with a planted aquarium for your discus, you need to look at how you plan to light it, depending on the size of the tank you choose, you will likely need anywhere from 2watts of light per gallon and up, you may also want to look into investing into a
CO2(Carbon Dioxide) injector to help keep your plants thriving.
Creating the Proper Conditions
The first point to mention in this section would be water temperature. Discus like their water warm, much warmer than many other tropical fish. Most Discus(S. heckeli) do well in temperatures ranging from 79-84F(26-29C), although the Heckel Discus(S. discus) need higher temperatures from 81-86F(27-30C).
The next topic would be with your chemical elements pertaining to water conditions. Discus are accustomed to very soft and slightly acidic waters. The total hardness of your water should range from 10-40ppm, and your pH should range from 6.0-6.5, if your water source is hard or alkaline you can help this by adding elements to soften the water such as aquarium safe peat moss, aquarium chemicals designed specifically to soften water, as well as adding extra plants to your aquarium. Another very important point about water conditions is the elements that are in relation to the nitrogen cycle, or bilogical filtration. This process produces three main components, Ammonia(
NH3), Nitrite(
NO2), and Nitrates(
NO3), both ammonia and nitrite is extremely toxic to most fish, and especially to discus. The third element to this, Nitrates, are not as toxic if kept at very low levels, if these levels get too high, this too can become toxic, so therefore you want to keep up with frequent water changes as was mentioned in the previous section.
Feeding
One thing to keep in mind when choosing foods for your Discus is the way these fish are designed, unlike many other NeoTropical Cichlids, Discus are not designed to be 'Gorge Feeders', they have very slender bodies, and a very tiny mouth so be sure to feed food that is the appropriate size, also you never want to give them large meals, smaller meals more frequently is always a much better idea. Also be sure not to have your Discus being fed one food too often, they can very easily become 'addicted' to one food and refuse all others, so be sure to keep the diet as varied as possible.
Finding dried or frozen foods that your Discus will accept can be a challenge, they are known to be very picky eaters, so basically, it may be a process of trial and error until you start finding foods that they will like. Another thing that is interesting about these fish is that they may go for quite some time without eating at all, this is normally nothing to worry about, although most keepers automatically panic. This can sometimes go on for up to a month, when, just as quickly as it ceased, feeding begins again, some people speculate this is to rid the body of built up waste products, but it is not entirely certain, but in most cases, unless the fish appears stressed, ill, or the water conditions are suffering, a Discus ceasing to feed is nothing to be overly concerned about.
Conclusion
If these fish are cared for properly, they will keep you in the hobby for many, many years. Discus aren't called 'The King of Aquarium Fish' for no reason, they're big, beautiful, and fascinating animals to care for, and to have in your home, almost nothing in the aquarium hobby has beauty that compares to that of a large tank filled with large, brightly colored, and healthy Discus. You can be certain that if kept happy and healthy, Discus are a fish that you will never tire of.
