The local rockery has Mexican Pop Rock which is porous and dried. Can I assume this would be ok to use as my base rocks? it's only 16 cents per pound which is real attractive.
Can you post a pic? What type of stone is it? I tried searching on Mexican Pop Rock, and get nothing but music and candy links . It sounds like it should work, but you'll want to make sure that it won't break down easily--many sedimentary rocks are not good in a tank.