Fish tail eaten?

[drufguard-1]

Hi- I have a few established freshwater fish in a 10 or 15 gallon tank that I took over for a neighbor that moved. There are 8 fish, 4 kinds. I think they are Zebra Danios, Neon Tetra, maybe Serpae Tetras and one other I can't find a photo for on the net - looks sort of like a Silver Dollar but has much longer fins...

I think I have the cleaning figured out and the water test are good.

The one Zebra Danio (that has shorter fins) appears to be having issues with the tail and fins. To me it looks like one of the other fish might be biting of the tail. I thought perhaps I had damaged it when I was first learning to clean the tank but now I think otherwise. It looked like the tail was growing but now it is definitely down to a stub, and I think the top fin is missing a lot of it now too. The fish (not sure if a he or she) is spending a lot of time hanging out on the bottom of the tank. At times it seems to have issues swimming, which I think would be hard with no tail.

Would one fish really bite off the tail of another? What should I do? I feel awful for the fish and don't want it to die. I don't see them being at all agressive with each other when I am looking at the tank.

Thanks

 

[FishGeek]

I think that it is possible that one of the Serpae Tetras or the other fish bit at the tail. But when I read that the top fin might be missing Fin Rot is also a possibility. Does it look like it is shredding away? You might want to look Fin Rot up and see if that is what your fish has. If its not and one of the other fish did it you should watch the tank for a little while and that will help you find the bully. Good Luck!

 

[discus4everGrl]

if it looks like the fish just flew through a fan then it's most likely fin rot.