Hello guys, one of my cardinals is missing the fin (please see pictures). Anyone might know the reason?
Population in the tank:
1 male guppy
Might be Fin Rot?
Guppies can fin nip which could lead to Fin Rot....I would get him some mates to keep him occupied!
Best try to quarantine the Cardinal....into fresh clean water and use a recommended treatment for Fin problems!
I would agree with @GHNelson and he is probably right, but it is a bit of a strange one IMO - for fin rot or nips I would expect it to be more ragged and something you would have observed earlier... and see it on other specimens as well - do you see any similar signs on any of the other cardinals or is it just this one?