Cultural gap indeed! I can't even find GS foam here in the stores; though I've heard some of the industrial warehouses have got it in stock.

I think the screen is fine, aluminium is relatively unreactive; but I will take a picture just to be safe.

Is marine epoxy safe for vivariums? How much do you think I might need for a tank that is 80 x 36 x 36 in cm?

Waterproofing paint sounds like a more aesthetic idea, but have you got any brands or any types of paint to recommend? Acrylic paint perhaps?

Drainage is my main concern right now. I could of course, limit the watering, but that doesn't seem foolproof.