Fibreglass as sealant for plywood question

[amule]

Hey all,

I know firstly i might get replies saying not to build with plywood for moisture reasons. I understand these reasons, and believe me, if i could afford to buy a large glass tank, i would!
I am looking into a way to seal this thing and although there are thousands of threads about sealant, i couldnt find what i was looking for.
I wanting to waterproof the inside and outer edges of my plywood/malamine(?) enclosure. I was thinking of using fibreglass to do so and as such have visited the local hardware store and bought some 450gm fibreglass mats and polyester resin (i looked at marine varnish but it was damn expensive and said it was non submersible, which didnt sound ideal for my enclosure as it will have a false bottom and possible some excess water (which of course will be drained). Although i believe myself to be quite capable of fibreglassing the enclosure, I had a thought that i might not have to use the fibreglass mats, but instead just use the polyester resin to seal the plywood (the way i WOULD have with the marine varnish.)
Does anyone have any experience with this, or forsee any reason it will not work?
Also any suggestions of something better would be muchly appreciated.

Thanks in advance,

Sam

[froggsong]

Wood is totally acceptable for large enclosures. I'd think you were nuts if you tried to spend so much on a glass one! The best thing to use is two part epoxy paint for potable water sources. This has been used successfully for fully filled aquaria for many years. If you are still worried about the bottom after that, you can line it with pond liner.

[beckdg]

wood is fine and i'd go with froggsongs suggestion.

as far as trying to adhere something to melamine to make it hold water... that's a bad idea. you can build something that is waterproof out of melamine and caulk the corners with silicone. however, as for making it HOLD water... that's a different story.

also fiberglass never really becomes 100% safe as far as i know.

[amule]

thanks for he replies guys,

Yeah im going to avoid the fibreglass. Its quite fiddly from what i know and it wont be worth the time. As opposed to going and buying a new tin of epoxy resin, would the polyester resin (for the fibreglass) work?

thanks again