Will let us know if something goes wrong. I'd start with a goldfish or two to start. And watch the ph !!
Will do! Not sure when I'll get around to putting them in. Hopefully sometime soon!
I used something very similar for a long time with no problems. They began as sandstone rocks about 1-2 feet in diameter and 6-8 inches thick but had splits all through them and I could easily split them down to 1-2 inch thick slabs with a stone hammer.
They just let off fine trails of bubbles for a day or two after first putting them in the tank.
Thanks for the advice. When you say "stone hammer", do you mean a 3lb sledge with a point? I did consider that I might be able to split them further if needed with a 3lb hammer and a cold chisel.=
Nice lookin rocks, and is that a "12oz Beer Bottle" for reference...

Thanks! ... I could have used a bomber instead but it might make them look smaller...
