Painting or sealing the inside of a wooden stand?

[targaboy78]

Hi guys,

I am in the early stages of putting together my 175G Bowfront Reef tank.
I will have a 33G sump inside my wooden stand and I am wondering if the bare plywood on the inside of the stand will experience rot or mold.

I am thinking about sealing the inside of the stand but I can't decide between a water-based Varathane or a Marine Varnish or a wood/deck sealant like Thompson's Water Seal.

Any thoughts or insights?
Tips or warnings?

TIA
Paul.

[sharkbait]

I wouldn't use outdoor water sealers. They repel water, but they don't seal it out like a urethane or a marine varnish. With an outdoor water sealer you're still going to get some moisture into the wood.

[captivereefs]

Use a product called marine spar varnish. It puts a nice heavy clear coat on the wood and works awesome! My local home depot had it.