Thanks in advance for your help.
2 weeks ago we converted our 25 gal. planted tank that had 3 small Discus ( 1 added 6 weeks before, 2 added 1 week before ) to a 65 gal. planted tank. Also in tank at that time 1 Red Tailed Shark, 1 Beta, 1 small Loach. The Loach disappeared 2 days after we...