So I just recently added CO2 to my tank and my pH dropped drastically. From a 7.8 to a 6! I'm not sure if this is the source of the issue, but I had never had issues with my pH before. I aerate the tank at night and leave the CO2 running in the daytime. I decided to leave it alone since I've read all over the place that although having the correct pH is important, having a steady one is more important. I also have a big driftwood in my tank that is probably making matters worse, but something is giving my betta fin rot. I change his water once-twice a week. He's in a cycled, heated and heavily planted aquarium with good water parameters except for the pH (API Master Testkit) but his tail seems to be getting worse. It just looked a little weird to the edges these past few days but I just got back home and saw a tiny little shred in his tail. He's so pretty and I don't wanna wait till things get worse to do something about this.