I‘m looking to make decorations and I‘m looking for stuff I can put into a mold paint an then place it in the water and have it last a lifetime. If this isn‘t safe for fish can you please tell me of a substance that has the properites I‘m looking for. Thanks
Resin is a good inert substance that holds up well. It can be mixed with sand, diatomaceous earth, or dolomite chips to create texture and volume. It may stick to a mold permanently unless you previously line the mold with wax paper.
