Originally Posted by Shortstuf888
it is the plants for sure! i had the same problem with my betta and he has extremely long and wavy fins. by looking at your pictures it looks like you have the glow in the dark plants, am i right? i had the exact same plants and it tore his fins up. you should never get plants that look spiky; if you use fake plants i suggest plants that look like grass or something similar. as for the tail biting, i have never heard of this i don't think this is the cause of the problem. you should try the pantyhose test. rub your plant across the pantyhose. if it rips then you know it would rip your betta fins. i hope i helped!
Tail biting does indeed exist. Just because you've never heard of it, doesn't mean that it isn't real. It is very common among Halfmoons, Deltas, and Veils.
I do agree, however, on the pantyhose idea.
Covermeinclay- It does look like he snagged it and ripped it clean on the plant, but it also looks like he may have either fin rot or tailbiting at the ends of his tail.