They are crazy!
An "Open Bottom Fish Tank"
here is a vid where a guy shows how he made his and you can watch him fill it with water. Bizarre! Cool though!
Apparently a lot of people are using these in ponds, so they can see some of their fish above the water occasionally :o
What do you think of those?? :O So crazy! It seems like it would be a bit more difficult to clean at the top, and you'd need to do big water changes, but at a small level it wouldn't be too big of a hassle!
hehe, my mind is blown by physics, pretty cool! It's interesting, I like that even if the power were to go out, it's not going to spill all over the floor XD