Originally Posted by
Filip
Another thing that strikes me besides Amonia and uncycled filter is your 90% daily WCs with straight tap water. This is not a good practice IMO and you should either start aging water(whole or at least half of it ) or lessen the % of WC .
Lastly , it may also be , that your discus has gotten some pathogen from the cycled sponges from your community tank that took advantage in their already comprimised immunity systems from Amonia and shocks from your daily big WCs with unaged water .