I was able to get a nice 75 gallon tank and stand combo this weekend. I also have a Fluval FX4 I plan to run with two aquaclear 110 HOB's. I am starting very slow as I don't want to be in the situation I was in this past spring with moving too fast with fish. My tap water is 7.8 out of the faucet. I am leaning to to toward some male/females groups of yellow labs, rusties, and maybe acei. However, I worried that my PH is not enough. I have read on multiple threads that pool filter sand is the way to go. However, I have also read that certain substrates like aragonite help with raising the ph. Is a PH of 7.8 to low to Mbuna? If so, should I try to raise the PH with an all aragonite substrate or pool filter sand with aragonite in the filters?