I hope this question is not too dumb, but in my high school advance carpentry class i made 10 bases out of solid oak with a plywood base with a "dip" or a "lip" that is 5/8 on most to be able to add habitat. Well i did a good job on the corners with it all being flush, but what do i put down on the bottom of the wood so i can add envirotex. Do i use some sort of Plexiglas or can i just pour it onto the wood and go form there. Hope this ist too dumb, but i cant figure it out haha

Thanks a lot Kevin