Poor diet is often to blame for fin nipping. Observation is the only way to ID the fin nippers. One way to reduce fin nipping is to include more protein (live food) in the fishes diet.
This can be caused by "fin nipping" between other fish or fin rot, which is caused by keeping fish in poor conditions.
I would take my fish to the vet and ask the Doctor to tell you why the fish has rotting fins
Males have longer and fuller fins and females have shorter fins
Easily. The males have the long colorful fins. The females have short fins.
Fin nipping is a symptom of poor feeding. Fix the problem by feeding the fish a bit more or more often or better food and the fins should recover.
Boys have big fins girls are small and have small fins =)
the size of it's fins and body
if its skin,eyes,and fins are not messed up.
It is pretty hard to tell. Wait until they get older then see which ones have longer fins, and shorter fins.
Yes, they can be. I had three females. One is a bully and stressed one of the other paradise fish to death and is now bullying the other one. She is also nipping at the fins of my betta and his fins are only half of what they used to be. A leopard danio also disappeared with out a trace and the female paradise is the main suspect.
by looking done where the tail or fins are
Just look between its fins, silly!