My aquarium has very high pH. I have never altered it and have kept a variety of fish over time. The pH (tested directly out of the tank, usually prior to a water change) is in the 7.6 range. Tap water is higher. My aquarium is planted, and I've kept a huge variety of fish over the time: barbs, danios, tetras, a betta, about 5 different types of loaches, celebese rainbows, platys, pictus catfish, cory catfish, white clouds, etc. From what I know, as long as the pH is stable, the fish usually adapt. I've never really read anywhere that advised altering pH unless you want to breed difficult fish or have a very finicky type of fish. Most fish that are tank bred are a little more adapted to tap water and can adapt. I currently have yoyo loaches which are wild caught, they're over a year old (in my aquarium) and are doing fine. Even the plants thrive. I wouldn't' worry about it unless you start to see a problem in your tank. Stable and slightly high is better than erratic and adding chemicals. Good luck!
