Don't do it! Just be patient, use a buffer to bring it up. Holey Rock will bring the PH way too high for you. See about getting one of the 7.0 buffers to stabilize your ph and provide some buffer capability to keep it stable.
How big is your tank fishfaery, anyway? And what type of fish are you planning to keep?

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Hm my reply didn't post. I'll try again.

Thanks for the advise on the rocks. That coulda been a costly, and big mistake. I'm timidly using PH UP currently. I'm cautious, not wanting a big PH jump all at once.

I have a 55 gallon bow front. It's running with a Rena SmartFilter and an extra little 10 gal spec filter just for extra water circulation.

I have fish already. Mostly livebearers and a mix of other peaceful community fish. Mix in a few inverts and frogs, plus a lot of live plants, and that's pretty much it.