Another newbie question...

I am in processing of collecting decor for my tank. The only free rocks (and I need free right now) I have available to me are granite. They look decent, but I am concerned about the weight. They are not boulders, but I could end up with 20 - 30# of rocks easily, since granite isn't exactly light. So, my question is: Since the tank frame lifts the bottom glass up from touching my stand's top surface, isn't it possible that the rocks could crack the bottom glass? Should I try to find some sort of rubber mat or something and cut it to fit just under the tank?

My tank is only 36x15x16 and the glass is 1/4" thick, as far as I can tell.

Thank you for your time...

Unless you are planning to nearly fill the tank with rocks it isn't likely that they will damage the tank. Their weight is reduced by the rock volume in water - a half cubic foot rock will push on the glass with its weight minus the weight of a half cubic foot of water (31 pounds). However I suggest you not drop a rock in the tank, just gently place it in position. I use granite rocks in my 45 gallon tank, with no problems.

you can also use a styrofoam pad under the sediment.

But adding it after the tank is set up?
Bit of an issue..........

Regards,
Tom Barr