Hi there. I've kept alot of different types of fish over the years including discus. So from my experience... Tank raised discus are not hard to keep if you remember that they are the stars of the tank and meet their needs. Lots of warm clean stabile ph water, low stress levels and good food.
A lot depends on whether you start with juveniles or adults. As has been well pointed out by previous posters.
You have a better chance of them being more tolerant of less than perfect conditions if you start with adults or subadults from a breeder. But regardless of what size/age they are you need to meet their needs more than those of their companions. They need warmer water (at least 82) and more water changes ( minimum once a week of about 50 percent for older fish (i prefer twice a week for adults) and more often the younger they are) than your average tropical fish. The more water changes the happier they will be and you will see it in their color and growth. They also like to be in schools of if possible at least six. This last time, I had 8 adults in my planted 120.
Especially for the first month or so that you have them they are easily stressed. This stress can result from other more aggressive or quick moving fish in the tank, to fish that "stalk" at night to just getting used to your presence. If overly stressed this can result in disease and death. Sadly in my experience, once they start to go downhill, things go from bad to very bad quickly and it is very difficult to bring them back.
I found it best to start a discus community tank with the discus only (bought from the same source at the same time is best) and let them make it their tank. Maybe with a bn.Then later on add in tankmates (that have been quarantined) such as a large school of rummeynoses or cardinals... even angel is ok if it's smaller than the discus and put in after they own the tank.
Lots of people keep all sorts of fish together. That doesn't mean that it;s best for the fish.. and usually they don't tell you whether the combo has worked for long periods of time. Years not months.. These fish have long life spans..I know lots of folks who have started with the community tank idea and once they got a school of beautiful discus in their tanks decided that "companions" other than bn would just take too much away from the discus and they made the tanks discus only tanks. They truely are magnificant fish..
I don't in any way mean to discourage you from discus. They are fantastic fish and I have probably enjoyed owning them more than any other fish I've had. But they do have more requirements than most other fish and if you commit to those than they will reward your efforts. I suggest that in addition to the valuable info provided on this site that you also check out simplydiscus.com, a site devoted specifically to these wonderful fish. Good luck with whatever you decide to do. HTH Sue
