I just bought 2 crowntail males from Walmart a few minutes ago, and just got home. All of the fish looked bad, the water was filthy; it was horrible. I just bought the 2 that looked the worst- one laying on his side floating on the top, and one laying on his side on the bottom. The guy that was laying on the bottom seems to have very advanced fin rot- it's about to start into his body, it seems. The little jar he came in is filled with blue debris that I can only assume is disintegrated fin debris. My local pet store is closed, but any suggestions on what to do to treat advanced fin rot? Medications?
The other guy was floating on the top and looks bloated right around his gills. I don't quite know what might be wrong with him.
Sorry for the trouble- I'm rather inexperienced at betta rescues, although I've treated sick fish of other species before. I just didn't want to leave them there to face certain death, though. They even had a bag with dead fish lying right in the sink for public viewing. So disgusting.
I am unable at this time to answer the questions regarding water parameters and frequency of changes, as I don't know what they were doing there. I'm going to go right now to put them into clean tanks with proper temps. Wish me luck with my new "children"!