Welcome to AA!
Chiming in a bit late, but let me see if I can be of help.
First, I don't know what your LFS's policy is, but if they'll accept returns maybe you could return the fish and let us get your tank cycled the easy way and work to figure out the pH problem. Just something to consider.
Now, onto your pH. That is unusual that your pH is so high. 8.5 out of the tap is even a bit strange, but it's manageable. I agree with fort, likely source is the substrate you chose. Do you think you could go on the website of the place you got it and identify exactly what it is you got? Some substrates come with some buffering built in, which can cause a slight increase in your pH, so that is entirely possible to be the cause.
The other thing it could be (very slight chance albeit) is that due to the presence of ammonia and nitrIte in your tank this can sometimes cause the pH test kit to read a little bit wacky too.