I've had my male betta Rosencrantz since Christmas 2009 and he's been the picture of health and personality, and about 3 weeks ago when I was doing a water change he caught a bit of his tail fin on the edge of his holding container and had a small nick in the middle closer to his body. I kept my eye on it and it didn't seem to affect him much but then later on, when I introduced a fake plant in his tank he got a larger tear in the fin from the end to mid-way up the length of his tail.
This tear frightened me a little more and I immediately took the plant out and did a water change, adding some aquarium salt and melafix just in case, though it showed no sign of fin rot and I additionally overfed him a bit as my petstore friend had had progress with this method.
A week passed and the tear didn't seem to grow any larger and the small nick appeared to be healing over and I did another water change as er the melafix instructions after putting some in everyday for that week. During this water change his fin tore more, from the original larger tear all the way to the nick, almost to the base of his tail. As this tear is basically splitting his back fin, I'm quite alarmed. I put more melafix in but is there anything else I can do? Through this all he's been acting like nothing's changed but I'm worried for him now. That last tear just occurred today so the water is obviously quite clean, being just changed.
There's a small piece of that last torn fin still attatched, here's a photo.
Please advise me on if he's going to be okay/suggestions.