Styrofoam - Is it safe? Advice please!

"Paul Dussault" wrote in message
...
Greetings,

I've recently moved my 77 gal. (24"x20"x16") from the 1st floor to the
basement. The tank is all glass, on a plywood/melamine stand.
I've often been advised to put a styrofoam board between the tank and
the
stand, to help reduce the stress on the bottom glass pane.
When moving the tank (which was in place for four years), I've noticed
that
the plywood of the stand had swollen a little in a corner, due to small
water spills; so I thought it would be a good idea to put styrofoam.
I was told that the styrofoam board should be 1/4" or 1/2" thick.
Unfortunately, none of the hardware "megastores" around here keeps
styrofoam
under 1" thick, and they wouldn't cut it to 1/2" either.
So I decided to go with 1". This styrofoam is quite hard and doesn't
"crumble" easily.

So now the tank is in place, with gravel, rockwork and water. No fish
yet.
It is almost perfectly level and the foam seems to bear it pretty well
(no
sinking).

But some questions are beginning to make me nervous:

- Is a styrofoam this thick will be safe over time? (ie is it possible
for
the tank to slowly sink in the styrofoam unevenly (due, for example, to
rockwork), causing stress to the bottom glass pane?
- Could the styrofoam eventually break or become damaged by occasional
small
water spills?

Should I empty the tank (again!) and remove the styrofoam, or can I
forget
about it and enjoy my mbunas?

Do some of you have any experience with styrofoam under your tanks?

Any advice would be greatly appreciated!
Thanks in advance,

Paul Dussault

Either your tank bottom is flat, or the bottom is higher and the tank
rests on it's sides. If the tank is sitting on the sides, these will
slowly sink into the styrofoam, perhaps as far as allowing the glass
bottom to contact the styrofoam. In either case, the weight will be
distributed very uniformly. Your concern about the rocks is
theoretically valid (causing the back to sink in deeper), but IMO, this
does not happen in any significant way. For example, if your 50 lbs of
rocks displaces 3 gallons of water (which weighs 25 lbs), then your rocks
are really only adding 25 lbs to that end of the tank. If the styrofoam
contacts the bottom glass, this will make it less likely for any glass
damage to occur from rockwork. Polystyrene (styrofoam) breaks down
(melts) very quickly from various chemicals, and slowly from UV exposure,
but in your application, styrofoam is IMO basically impervious to water
spills.

NetMax