Rock/Stone for set up

I've been trying to hold off on buying anything until I can get to the landscape supply when they're open. It's been kind of tough. I've got 40 lbs. of sand in the tank with the power heads, and about 60 gallons of water. It's just bellow the point where I can turn on the power filters they'll suck in air otherwise. It's cycling with just power heads, water and sand at the moment. I'd fill it up to turn on the filters but I don't want to waste water. I know I'll have to take some out when I put the rock in if I did that.

They are fairly thick and each one is 1.5'x1.5' and sn inch thick.

That rock should be fine. Sandstone is fairly inert.
I would say have some patience and wait for the landscape place to open. That sandstone is pretty expensive rock for a fish tank!

I've been looking for rock/stone to put in the tank for hardscape. The landscaping supply place I went to has been closed the last three days. Anyone know a good place to find decent sized rock/stones for a setup?

I looked at home depot and found this www.homedepot.com/p/MS-International-Rus...STEPSTONE/202194425#

I'm a little worried it might raise the ph to much.