help with betta fish fin splitting

[coltin]

I'm trying to help crafton figure out the best course of action for his betta's fin issues, and I was wondering if you could clarify a few things about using aquarium salt.

How much salt did you actually add to your tank, and did you follow a specific dosage? I've read that you can add 1 heaped tablespoon of salt per 20 litres of water, and if that doesn't work, you can double the dose after 48 hours. But I'm not sure if that's the right approach for a betta tank.

Also, I've heard that you should keep the salt level consistent for at least 2 weeks, but no longer than 4 weeks to avoid kidney damage. And when you stop using the salt, you should do a series of water changes to dilute the salt out of the tank. Does that sound right to you?

It would be great if you could share your experience with using aquarium salt, and if you have any advice for crafton on how to use it effectively.

[crafton]

I've added 1.5 teaspoons of API aquarium salt to the tank, and when I do a water change, I replace the salt at a rate of 0.5 teaspoons per gallon. Since the tank is 3.5 gallons, I'm trying to keep the salt level consistent. I started the salt treatment on August 1st, so I'm getting a bit worried that it's been in the tank for too long. I've just got one male betta in there, and I've noticed he's been chasing his tail - last night, he even jumped at it, and I think he's started biting his fins now.