Polystyrene Board Thickness To Level Tank

[white_and_nerdy]

My new tank is 60" long and 15" wide - so it'll hold around 280 litres of water. The glass itself weighs a lot. I'm in the process of purchasing some polystyrene boards but I'm not sure on what thickness to get.

I can get 25mm, 50mm or 75mm. I'd like to include some tolerance in the thickness for compression of the material from the tank's weight.

 

[PERCY]

My 5 x 1.5 x 2ft, approx 450 litre was delivered today. The guys from the fish store supplied polystyrene for it. It was no more than 5mm thick. It was just squares approx 300 x 300mm. The price on them were 30 pence each

 

[tribalbrit]

Polystyrene wont level your tank. it will compress equally. You need to level what the tank is on first. Polystyrene is ok for cushioning the tank base to prevent any bits of grit from damaging the base. Any thickness will be fine. If the tank has a floating base ie; is higher than the frame it sits in then no polystyrene is required.

 

[white_and_nerdy]

Polystyrene wont level your tank. it will compress equally. You need to level what the tank is on first. Polystyrene is ok for cushioning the tank base to prevent any bits of grit from damaging the base. Any thickness will be fine. If the tank has a floating base ie; is higher than the frame it sits in then no polystyrene is required.

The cabinet and the floor is level I'll order some 10mm sheets. I was thinking of 20mm but that may be too much.

 

[tribalbrit]

even the old type polystyrene ceiling tiles are thick enough, not sure if you can still buy them though.

 

[white_and_nerdy]

Is polystyrene safe to use underneath a glass tank?

 

[tribalbrit]

Is polystyrene safe to use underneath a glass tank?

Why wouldn't it be?

 

[white_and_nerdy]

Is polystyrene safe to use underneath a glass tank?

Why wouldn't it be?

I read online somewhere earlier about glass and acrylic. Just thought I'd check Would 8mm or 10mm be enough? I've heard not to have polystyrene that's too thick.

Edit: Here's the link. It says "Putting padding under a tank is recommended for acrylic not glass".

Another quotation: "Padding under a glass tank will cause uneven stress on the tank. I have a few 100+ sized thanks and have never in 25 yrs had a problem with them. Acrylic on the other hand requires the padding to help distribute the pressure of the tank across more surface area, that is why acrylic tanks
have a flat bottom and glass have a raised one".

 

[tribalbrit]

If the bottom of your tank is raised you do not need polystyrene under it.

 

[white_and_nerdy]

If the bottom of your tank is raised you do not need polystyrene under it.

I've checked the tank and the bottom pane of glass is sitting directly on the cabinet - there's no raised area.

 

[OldMan47]

Polystyrene cannot be used to level a tank at all. It can be used to cushion a tank that is designed to be supported directly by the bottom glass to prevent localized stress points on that glass. If you actually need to level a tank, use solid shims under the stand, not the tank.
If you have a level stand and merely need to cushion your tank, as little as 0.5 cm is probably thick enough but a bit thicker would not hurt one bit. It would allow for slightly larger surface imperfections in the stand.