The rummy's will tell you that the water conditions are off by the colour loss on their face, you should check the KH or PH on your tank, rummy's like soft water conditions and a neutral PH 5.0 to 7.5. Your discus need calm water, you should take the air intake out from the back of your tank to calm the water, and you'll see that the discus will start to move around. Just trying to help. try peatmoss extract to soften the water its what i use for my tank i got cardinal lemon & rummy tetras.

i think theres way too much water movement.. lol

The noses on your rummynoses should be bright red, there must be something wrong with your setup, the bubble wad prolly for starters