How to Place Overhead Filters

[H]-[H]

I need advice on placing two overhead filters(2.5ft x 5inch x 6inch) on my tank(4' x 2' x 2')
I have two pieces of custom cut arylic(26inch x 4inch x 0.3inch) placed across the tank and when I placed both overhead filters on top, the acrylic bends in the middle.. I tried stacking both acrylic pieces together and it still bends..
If I replace the acrylic with glass of the same size, will it hold the weight and not bend?
My tank doesn't have a top cover so I can have easy access to the filters..
Any ideas on how to fix this problem is greatly appreciated.. Thanks in advance.

 

[markstrimaran]

I have a 18" x 6 x 12 filter box on top. It is supported with 1/2" acrylic with a center brace. It bows a little.
Glass would flex less, than acrylic, if you can find 1/4" tempered glass. Better yet.

Or glue stringer on to the acrylic.

 

[H]-[H]

Previously, the two overhead filters were placed on the center brace(a piece of 1/8" glass) and it held with no problems..
It was until one day I saw a post here about a tank build and realized that the center brace is for holding the tank from breaking and not for the purpose of putting filters, let alone two heavy ones..
The reason I went with acrylic pieces as support was because I was under the impression that acrylic is stronger than glass.. so how is it that acrylic would flex/bow but not glass?

 

[markstrimaran]

Well acrylic is only stronger in so much, that it will bend alot, before failing.

Inch thick glass will stop bullets, but it would take alot more acrylic.

1/4 tempered glass is about 50 times more rigid than 1/4" acrylic.
A 48×20 span of tempered glass supported on the ends will hold 200 pounds, were the acrylic would bow, until the center curved out.
The difference is in the severity of failure.

 

[H]-[H]

I'm guessing it would be much more expensive to get tempered glass of the same size as the acrylic?

 

[markstrimaran]

I find it for free, old 55 gallons curb tanks, glass doors on old entertainment stands. Shelving, end tables.