Originally Posted by lightupthedarkness30
I'm trying to setup a DIY cheap build and I have a lot of sandstone that I could make into some awesome formations. Is sandstone safe to use? And what kind of silicon would I need to use to glue together?
The silicone should be 100% silicone.
GE silicone 1 (windows and doors) check and make sure that it doesn't have any extra added chemicals our it can kill your fish. Meegosh is right it can raise the Ph in your tank