An Upsetting Discovery

I went to feed Casper yesterday and noticed a tiny hole in his dorsal fin. There are a number of things that could cause this - fin rot, ammonia poisoning, sharp decorations in the tank, over flaring. I tested the water parameters and everything looked good, so I don't think it's fin rot or ammonia poisoning. To play it safe, I treated the water with some betta spa (contains Indian Almond Leaf). This morning when I checked on him he had a tear in addition to the hole!

Here you can see the tear and the hole (kinda...he doesn't like stay still). I'm suspecting that there is something in the tank he's catching his fin on, so today I will remove him and thoroughly inspect everything and do the "pantyhose test" (run pantyhose over the objects in the tank, and if they snag the object is unsafe for betta fins).

He is eating and acting normal, but I don't think I should breed him until after his fins are completely healed. Betta breeding is no joke - both parties typically get very beat up during the process - so they need to be in good shape before they go into it. Fortunately, Neptune Nebula has been making some beautiful bubble nests and looks to be in great shape, so I should still be able to go forward with next week's breeding with him and Rain.

In the meantime, Casper will get some extra special treatment until his fin is healed: water changes every 3 days, and extra dose of stress coat, and 3 feedings per day.