Possible Fin Rot?

[bex1]

hey i bought 2 peppered corys 2 days ago tho go with the other 3 i have in my community tank. i have a small 5 gallon tank so i decided to quarrantine them along with a african dwarf frog i bought, before they go in my main tank (see sig).
one of the peppered corys has part of his tail missing, he was like this when i bought him.
theres no redness or anything and he is eating etc, theres nothing else wrong with him apart from his tail, could it be fin rot or could he have been bitten by some other fish before i got him
my quarrantine tank stats are:
ammonia 0
nitrite 0
nitrate 20
pH 7.2
temp 26 oc

thanks for your help, cheers
x x x

 

[dwarfgourami]

one of the peppered corys has part of his tail missing, he was like this when i bought him.
theres no redness or anything and he is eating etc, theres nothing else wrong with him apart from his tail, could it be fin rot or could he have been bitten by some other fish before i got him

Hard to tell, could be either. Either way, the best thing for him is clean water. If you notice it getting worse, then clearly it will be finrot and you will need to treat for that.

 

[WILDER]

Corys are prone to bacterial infections so i would treat with a bacterial med like myxazin, good luck.