betta tail splitting

Question
QUESTION: I have a betta fish that I got from a pet store about ten months ago.  He lives in a 5 gallon tank, with a filter system, he gets water changes of 1/3 of the water about every other week, with treated water.  He is very active.  He gets 3-4 beta food pellets every day.  He has never been ill.  The problem is that his tail is splitting.  He has lost about 1/4 of his tail, and the rest is kind of ragged.  It has been a slowly progressive affair, which started soon after I got him.  There don't seem to be any black spots or discolorations.  I have treated him twice with medications, the last time with a 2 different medications, made for tail rot.  Anyway, I don't know what to do.  He doesn't seem to be upset, and swims quite a lot every day.

ANSWER: You might want to try a combination of Maracyn and Maracyn-2. You can buy them at your local petstore and they are stronger than most Betta medication.

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QUESTION: Thanks for your answer.  Actually, I have already tried maracin and maracin 2 at the same time, without effect.  Any other suggestions?
Kevin

Answer
Theres a number of different products you can try for fin and tail rot, but you might have to order them online if you can't purchase them at your pet store. Try Trisulfa by Mardel or Tetracycline by Aquafish. Your best bet to kill the disease is to just keep on it, you might have better luck with a different product.

You can also add some Aquarium Salt to the water with the medication, I've seen great improvements in the health of my fish when this is used in combination to medicine. Good luck, I'll keep my fingers crossed for you.