Hello. I recently lost a discus - it began swimming erratically and died 2 days later. I have an 85 gallon tank with some neons (12) and a pleco (he's small) and now one remaining discus. The pleco hides nearly all the time. The discus died yesterday. Today the remaining discus just swam like crazy and I am afraid he/she will die. The tank tests perfectly. No accumulation of ammonia, nitrite, or nitrate. pH is around 6.5. There are lots of plants and the bottom is sand. Can anyone suggest anything? I've had the discus for at least 3 months, they are smallish. So heartbreaking!! Thank you
