Discus Issue

[Bastler]

Hey all

I'm new to discus fish.

I have a 4ft planted tank just with DIY CO2, A canister filter and two 150w heaters. The tank is about 200L.

I had a bumble bee cat fish, one pleco and a bristlenose and at this stage one discus. However i bought four new discus and none of them looked good but they were bought from a friend of a friend etc so i took them. One of them I believe had a fungal issue or something as it had alot of white around its mouth and gills but i did not notice this till the next morning.

Basically all but one discus died. I did about a 80% water change cleaned out the filter. I did a 25% water change every 3 days to hopefully solve the issue. But this discus fish just keeps hiding and has very dark stripes and is very dark itself.

I took out the bumble bee thinking mayb he was causing stress. I got $30 for him and just got some neon tetras and a couple swords. They are all fine but the discus is still sulking. It does eat but not much and just does not have the colours that you see in pics.

Any help would be much help.

PH is 6.7-6.8
amonia is 0

Everything seems fine i just cant work it out..


Cheeers,