Cement leeching

[Viper]

A good tip but not pratical for something as large as a DIY cement background/wall.
Would be to put it in the back of your toilet.
Just make sure you can still flush it properly.
You would cycle the water as many times as you flush your toilet

I'm not sure you quite understand how buoyant this stuff is. Although that is an extremely clever idea (one that I might use for any future artifacts that need to be presoaked before being put in the aquarium ). The water doesn't reach the very top of the back of the toilet though so there will still be some parts sticking out of the water. My dad and I had around 70 pounds of weights trying to hold half of the background (it was in two pieces prior to being put in my tank) under water in the utility sink in my basement. The foam was still moving around and floating up to the surface. I tried just holding the foam under the water with my bare hands and it still would wiggle and move around under the water (chipping some of the cement off of the corners :censor. I'm 220 pounds btw so I had a good amount of force being applied to that sucker too!