i have one fish who always seem to have a problem with tail splits.my water params are very good still hes the only one with this problem.[theres two more fish with him]this is the second time that ive tried adding melafix and each time the two fish with healthy fins get split ends,when i discontinue the melafix their fins heal back up.dont know why this is happening,hoping one of you guys can shed some light on this for me.

That is perplexing. I had a bad experience with Melafix and won't use it again. I know that most people love it and say it is a "miracle" cure but it actually burned one of my fish.

I have an orange fantail who is more sensitive and is just not as healthy as my other fish. She became very lethargic when I treated the tank with Melafix for her torn tail. It didn't help so I did a huge water change, added back charcoal and she turned almost completely black! She looked like someone handled her with motor oil. The black is healing tissue after whatever has caused the problem is gone.

Her tail finally got better on its own and grew back. A big chunk of it was missing.

I don't know what to suggest to you since your water params are fine. Just keep up with 25% weekly water changes. And some fish are affected by their genetics. no matter how excellent the care we can give them.

thanks for replying wynkin,i dont understand it either i guess i must have some sensitive fish.

Just a suggestion and it may not be a good one, but would salt help? At least reduce any stress....

coudl split tails mean there is another fish which is bullyign it?
my ranchu use to bully my fantail and nip its tail all the time. after seperatign it and putting it in a bowl and then introducign him into the tank again, the bullying stopped, and there was no sign of tail splitting anymore.

just a sugguestion

I would agree that salt would probably help, at least protect and heal and reduce toxicity.
Strange, very strange.... i wish i could help! But you've got some great ideas here!!

What are your water parameters ?

my water params are ammonia 0,nitrites 0,nitrates 20 or a little under,ph 7.6.i do not see any other fish bully him,this only happens if i add melafix.thanks everybody for your help.