I have a 10 gallon tank that had 2 bettas in it with a divider. One of the bettas (Finn) got dropsy. I moved his tank mate (Angel) to a 2.5 gallon as soon as I saw symptoms so that she wouldn't get it. I heard it's highly contagious?
Finn passed away yesterday and I'm hesitant to just drop Angel into the tank they were in. How should I clean it? Will a 50% water change be enough or do I need to start the tank from scratch? I'm not sure of what to do..