What plywood thickness do I need to help support my aquaria?

[Saint_abyssal]

I've been planning a rack of aquaria for a while now. I'm going to use a Uline widespan wire rack with wood laid over the shelves to better distribute the weight. My original plan involved large tanks supported by sections of "two by" lumber laid across the rack. Since then, I've revised my plans to use smaller tanks as pictured in the diagram below. I was hoping to be able to use thinner wood, like plywood to give me some more head room in the shelves, but I don't know how thin I can go before it's too weak to support the tanks. What thickness should I go with? Or do I need to stick with the original "two by" plan?

 

[Back in the fold]

Thickest is always best so it doesn’t bow or warp . Use 3/4 inch . An added plus is that it insulates the bottom of the aquariums somewhat .

 

[GaryE]

I also prefer 3/4. It costs a bit more, but it's considerably more solid than 1/2. Be certain with the metal framed rack that it doesn't wobble in any direction. Not all of them are well made, and I don't know that brand.

 

[Back in the fold]

I also prefer 3/4. It costs a bit more, but it's considerably more solid than 1/2. Be certain with the metal framed rack that it doesn't wobble in any direction. Not all of them are well made, and I don't know that brand.

Yes , that’s good advice about checking the rack for structural integrity . Figure your weight and add 20% for insurance and then see if the manufacturer lists weight limits . There’s a lot riding on that and having it tumble down would be catastrophic . Cheap ones will hold at first but gradually weaken then give way when you’re not around .

 

[MaloK]

I would install cross braces in the back and sides and use minimum 3/4 inch cabinet grade plywood (Hardwood) or better marine grade plywood.

The weight rating per shelves is excellent, my only concern would be integral rigidity.