jamesleagas wrote:this is my roma 240 which has very good stock and as u can see the discus spread out nicely and are very comfortable and confident
Yes, but those aren't wilds.
I'm not a huge fan of planted discus tanks as even though mine is planted (mostly wilds with a couple of Cuipera Crosses from Forrest). The main reason being that if your discus get ill or stop eating the first advice you get is to raise to temps....to 29 or 30 degrees C. In most instances, in a couple of weeks you have almost no plants left. I had a very nice planted tank initially until one of the Heckels went off its food and I raised the temps and now my tanks has mostly Fissidens with a couple of Anubias nana.
Anyway, having said that, having no plants doesn't mean unscaped. My tank has loads of Manzanita. The other thing is lighting. With wilds, a brightly light tank which is mostly bare can cause them to dash wildly when the lights come on causing them to injury themselves and lead to infection.
So my advice would be to add some wood where they can hide (Darrel's suggestion of floating plants is good too), and lower the lighting, since you don't have any plants.
With domestics, they are used to being crowded and disturbed (see all those 99% water changes on youtube) and they just don't care. They also can live in harder water than a lot of the wilds.
Oh to get back to the original question, I've had Sterbai cories in my discus tank since day 1 and they have bred over and over. They seem to even thrive in the 30 degree C range when I've had the temps up there. Currently my tank is at 28 C.