Bettafix for fin rot - betta

[Kaitlynleigh98]

I have a Betta fish, red half moon named Pidge. He has fin rot, I’ve been doing a 50% water change daily for about a week, it’s a 3.5 gallon tank. I haven’t seen significant changes in his condition so I got bettafix, it was recommended by a coworker. I was wondering if I need to add the medication now and THEN do the 50% water change? Or do the water change and THEN add the betta fix?

 

[SaraB]

I would add it to the new water after a water change. Also take out any carbon that's in your filter.