On Wed, 27 Aug 2003 10:33:37 +0100, "Ned" wrote:

Have you built one with ply Andy?

I've only used solid timber for vivaria and acquaria stands, with a
little ply for making cabinet doors or tops. For the enclosure itself
I've used glass (or mirror), because it's easier to clean and quite
easy to assemble with (the right) silicone.

Terraria are easier to make than aquaria, because the weight of water
is enormous. Even a few big rocks is still lighter than a box entirely
full of water.

If you're making a desert terrarium, then you could make the base from
marine ply. Personally I wouldn't, because I'm still somewhat wary
about potential warping, and it's also a nuisance to join glass sides
to a wooden base. A terrarium still needs to be water resistant.
Cleaning is a wet process, even for a desert terrarium, and spills are
inevitable. If you ever have infection problems, turf the inhabitants
out, lift out the rocks, then carry the whole glass box outdoors and
hosepipe it.

Chipboard is just absolute rubbish within a few feet of water, no
matter what you do to it. If you insist, use Contiplas (melamine
faced) rather than Contiboard (wood veneer). Chipboard with weight on
it also sags over time. Damp chipboard in a similar state does it
while you watch.

What finishing do you have to apply?

Poly varnish is a good start. Avoid yacht & spar varnish, as many of
those of optimised for flexibility, not water resistance.

Best of the lot, and the only stuff I'd trust to seal the plywood
floor, would be Rustin's Plastic Coating, either floor or bar grade.
Stinks like a Komodo dragon's latrine when you apply it, but the fumes
clear up a lot faster than poly's too.