Hello, I have most of what I need to start my 3d rock background. I plan to use real rock as well as spray foam.. The only thing I am not sure of is what to use for a protective clear coat. This will be for a 155 gallon tank so price is an object! Thank you
There's some food grade epoxy available from a couple of manufacturers - it is labeled as "drinking water tank epoxy coating". Color additives are available as well. Most of them are 2 part so you will have to plan ahead and work with small batches; some of the epoxy is quite noxious while curing - a well vented workspace will be required, it also requires a temperature above a certain minimum in order to cure properly so outside is not an option unless you wait until may - june. Most of it can be spray painted if you got the right equipment.