tusk's fin

[dlight692000]

my harlequin tusk's left fin (yellow) almost looks grey or tattered(is that a word o well) any suggestions
my tank, 50 lbs of lr, crush coral, wetdry,skimmer sump with a powehead in the tank(put in yesterday)
tank mates- golden puffer, clown trigger, xxl yellow tang and 3 damsels in a 125g

 

[dlight692000]

i will put him in the 20 g thanks a bunch
i just hope he is welcomed back into the 125 with open fins not open jaws