The water that comes out of my tap is about 8.5. In my 75 gallon tank, I have South American Cichlids and I know they like a more acidic water. I bought Fluval Peat Granules to lower my pH they will arrive soon but I do water changes once a week about 30%. Will the peat have time to lower the pH before the next water change or will it be useless since I will be changing the water and it will revert back to a higher pH? Any ideas to keep the pH smoothly at about 6.8-7? My fish are also showing signs of not enjoying this high pH so I think it is a problem.