What type fo mortar does one buy to set a plastic tub into to make it a bit more solid underfoot? This would be on top of a plywood subfloor.

Thanks?

Flickit

...thinset (for laying ceramic tile), but make certain the plastic tub is not sensitive to the ingredients in the mortar.

speedball1

We just use regular cement and set the tub on it and leave it alone until it sets up. Tom