Thanks for that!

I need about 3/4 sealed and 1/4 mesh, need to keep the humidity up. So I would divide it into - 6 inches siliconed-in bottom portion, for substrate or false bottom, 12 inches opening door and the top 6 inches for the mesh. Something like that anyway! (Approximate measurements obviously)

I would probably make a perspex frame for the mesh and just silcone or glue the mesh on, the mesh I have is a lightweight plastic type, so wouldn't be a problem hopefully!

Do you think the perspex would warp over time? I need to keep it flush as possible so that I don't have any escapees!