My betta, Norman, is not doing well. He is in a 1 1/2 gallon bowl with rocks and a live plant on the bottom. There is also a sweet potato vine at the top (I keep the roots trimmed and he's always liked to hide in the roots). For the last several days he has been very lethargic, just sitting at the top of the water. I changed his water three nights ago, giving him a dose of BettaFix for the first time. The next evening he had one popeye. I purchased some Erythromycin yesterday and also a tank heater (Hydor Mini Heater, 7.5 Watts). Yesterday afternoon I administered a dose of Erythromycin and added the heater. The heater brought the tank up to 80 (it was right around 70). This morning, Norman is lying at the bottom breathing heavily and slowly coming up for air every few minutes, then sinking back to the bottom. I am planning to do a 100% water change this morning and treat with Erythromycin again. What do you think is going on and should I be doing anything else (Epsom Salt, Aquarium Salt (Never done salt treatments before), BettaFix, etc.)
Probably a contributing factor to this is three weeks ago we were out of town for the weekend. Norman had an apple snail tankmate that died over the weekend. When I came home, I immediately took out the dead snail and did a water change. For the next two weeks, the water got unusually dirty. This week, it had finally appeared to equalize.
Any help would be greatly appreciated. I am really worried about Norman and don't want him to suffer. Thank you!!