PH, is extremely important. Some fishes can with stand the high pH just like yours. Angels, dwarf gouramis, and many other delicate like fishes, need a pH of 6.8-7.0 Although it is rare that if you have angels in your tank with that high amount of pH, that they can survive it.
Although, pH is meaning how acidic the water is.
I believe that if you were to raise fishes, you would need a higher pH, just like yours, but that is because young need that high amount of pH.
Pleco (
Hypostomus Plecostomus they can survive at a higher amount of pH.
Although raising plecos are even harder than raising a young 3" pleco. I don't know why, but plecos' are easy to raise when they are older, but when they are still babies, that could be hard.
Also, you can always try and add some live plants, they help neutralize heavy metals, and many other things.
Very few plants in my experimentation has been proven to lower, and raise up the pH to a certain level.
Although most of my plant experiments have just proven to neutralize the
chlorine, and gather up heavy metals. Plants need these types to survive too
