I've had really persistent fin rot issues with my betta despite daily water changes. The tank is cycled. My water has .25 ppm ammonia out of the tap, so I use Prime to condition it. I've posted about it ad nauseum on multiple forums and I've tried a ton of different things to treat it. I was having an issue with the pH being 8.0-8.2 even though it was coming out of the tap at 7.4-7.6. I had that figured out (or so I thought...maybe it was decaying plants in the gravel?) and the pH was stable at 7.4-7.6 every day for a month. I tested my betta's AND my Jack Dempsey's water parameters daily for almost a month and everything was looking perfect so I stopped testing. Lately my JD has been acting kinda...meh. He's still eating, looks healthy enough, but he's not as active as he was before and less excited when I come up to the tank. On a hunch, I tested both tank's pH levels last night and they were 7.8 and 8.0. Then I tested my tap water and it was 7.8. I bought a GH/KH test kit and it tested very low for both. Both of these fish thrive in pH of around 7. I know that both can survive at higher pH, but my betta is never gonna kick this fin rot with a high pH, and I miss seeing my Jack Dempsey all riled up and active. Is RO water the solution? I'm seriously considering buying an RO filter. I'm actually moving to a new place in 2 weeks, and I'm hoping that maybe the issue has something to do with the pipes and the water at the new place will be better quality. It's in the same city but a different area. I know there are some cons to RO water, one of which being the lack of nutrients. What would I need to add if I start using RO water? Also I've heard that RO water doesn't always have a stable pH. Not entirely sure how this works. I have 2 large pieces of Malaysian driftwood that I'm going to add to the JD's tank once we're in the new place, and that should help bring the pH down a little bit. But I can't really put driftwood in with the betta because it will further damage his fins. Stupid water quality!!!! I've worked so hard and spent so much money to try to keep these fish happy and healthy and my darn tap water is ruining everything!!!