Discus Cloudy Eye

Hello I recently introduced discus to my 190 L juwel trigon set up. Unfortunately one of them has developed cloudy eye I also seen that the other smaller one fin is sticking to his side and has some white bits.

The set up:
Tank Volume: 190 L

Filtration:
Internal:
Juwel bioflow 3.0

External:
Fluval fx6
Fluval g6
Fluval 406
All Pond solutions 2000

So there is plenty filtration, filters are regularly cleaned and media changed according to schedule. Currently using fluval carbon, Fluval clearmax, jbl bio nitratex, jbl tormec, and fluval g6 tri ex cartdridge. On top of that plenty bio balls.

Substrate:
Jbl Soil underneath and on top Jbl river sand.

Decoration:
Few plants and bogwood

Fish in the tank:
6 discus in size between 3 and 4 inch
12 Neon Tetras
4 corys
3 rams
4 little clown loaches but they will be moving out soon
1 gold nugget pleco

Water parameters:
Conductivity: 300
Ph: 7.2
GH: 80
KH: 50
Ammonia: less than 15 mg
No2: 0
No3: 20

Water changes normally Wednesday and Sunday 50% or more if required according to conductivity.
Currently because of the cloudy eye 90% water change daily up until Saturday. If symptoms won’t cease by Saturday will remove carbo from filter and will treat with seachem kanaplex or api furan 2.

Does anyone have any suggestions? Is there something I’m doing wrong? Should I maybe remove all tank mates and introduce few more discus once cloudy eye cured?