<a href=showthread.php?s=&postid=11984432#post11984432 target=_blank>Originally posted</a> by crazzy
This question has been asked many times and I fail to understand why people will give this question a very wrong answer which can become a disaster with the tank disintegrating / failing. Some tanks, mostly the glass ones are built with the bottom sheet of glass "floating" inside the outer edges or vertical panes of Glass. They are designed this way and the outer vertical panes must rest on "solid ground" If you put a soft foam or rubber under this type of design you will put pressure on the bottom "floating" pane of glass thereby causing it to shatter / crack or split from its sidewall seems because of the external pressure on the pane upwards. You cannot and should not listen to blanket advise statements that are not qualified from this very dangerous perspective.
You may have a tank that will benefit from foam, but depending upon its design you may have a tank that will become a disaster because of its design if you put foam under it.
This has been answered many times before. It is wise or fooloish depending upon the tank you have!