Good point. True, that would wery much suck.
Attaching it to the wall will be no problem, i will do that.
Dont know about attaching it to the floor but i will keep that in mind.
I just bought a book online about building this and that for pets, includding tank stands, mabe it has some other pointers aswell. But it wount arrive untill next month, wich is ok, im in no hurry. This is my first attempt and i want it to be succesfull.