Last night I checked the pH on my 3 gallon Iwagumi (the one as my profile pic) with 7 chili rasboras... and it was at a hideous 8.2 :eek5:! I feel like a terrible aquarium keeper for slacking so much on my testing :icon_roll, but, despite being a black-water species, the chilis seemed to be acting normal, except for one who wasn't eating (this was probably because I did a major trim and destroyed lots of hiding spots. I added more floating plants and he seems to be acting normal again.) The pH jumped so high probably because I took the tank off of CO2 and am now just using Flourish Excel once a day. The raise was so slow it hasn't stressed the fish...yet. So how do I lower the pH? Is the best way to just add CO2 again? I don't really want to add any chemicals and complicate things more. Also, I think the pH used to 7.2 before I took of the CO2...still a little high, but they did great at that level.