I have found that ph for most fish bought stateside either from garage breeders like me or fish farms that sell to your LFS are mostly raising fish in a ph of 7 or so. Ph is really not as big a deal for alot of species as it used to be say 20 yrs ago when alot of these cichlids were being caught in the wild. Discus for example used to be almost exclusively wild fish and so the ph and other water parems for these fish were critical, now that they are being bred and raised stateside in giant ponds or holding tanks with a ph of 7 just having the ph be stable is much more important in my opinion than the number your test kit reads. I have not noticed the color differences when it comes to ph. If i had to guess i would say that you would probably not notice a big difference in your fish unless the ph was way high or way low out of your particular fish's requirements for example a discus that needs 6.5 ph and you put it in a ph of 8.5. Fish would likely have terriable color and be poorly overall. But same fish in 7 you might not see any problems. I know some of my fish really colored up when i turned the heat up . I had some dwarfs (blue rams) and saw a huge improvement in color and activity of these fish when i raised temp from 82 up to 86. Fish were much happier and twice as vivid in colors.
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