JackGulley’s South American Tank! (Under Construction)

[JackGulley]

They did, and I removed some water. The sand all fell in in one chunk and splashed the wall.

 

[GaryE]

I've done that a couple of times when refilling after a change. It's messy. I like to give a tank at least to the base of the black trim. In a rimless tank, I give it a few cm at least, sometimes more. Air filtration moves water, and also creates mist right above the waterline. The tiny droplets can travel.