My mother has a betta that now has popeye. I brought him to my apartment so I could monitor the meds for the tank. He is just in a little 2 gallon tank with no plants or filter (we completely change his water once a week) but he does have a heater, which usually has his tank at around 74-76 degrees. When I first brought him to my apartment inly one of his eyes appeared to be affected. Because the maracyn packets were meant for a 10 gallon tank, I mixed one packet with 100 mL of water and each day added 20 mL of the solution to the tank (5 days). Yesterday was the last day and the betta now had a large red lump on his head. When he gets agitated, he seems to sort of dart so I think it might be an injury. Today, the lump appears smaller and less red but I am keeping an eye on it. Unfortunately today, the other eye now seems to be affected. I just did a complete water change for him because he was no longer supposed to be on medication. I will attach pictures from yesterday and today. But what should I do? I've treated fish with popeye before and the medication worked. Is it because I mixed it with water? Should I have done that fresh every day?


