Lid with holes for emergent plants?

[Ch4rlie]

You don't need any expensive supper strong plastic for the lid. Standard acrylic will work as long as it stays cool and is thick enough. Yes acrylic will warp you put something hot on it like a lamp. However if the lamp is 2 to 3 inches above the plastic lid it will stay cool. and won't warp.

You also want it thick enough to so gravity doesn't cause it to sag in the middle of a large tank. 1/4" thick sheet should work while 1/8" will work for smaller tanks.

I’ve tried 3mm or 1/8” plastic acrylic or Perspex sheeting, this was for a nano tank lid cover, can assure you it definitely does warp along edges even though light was at least 6” above the sheet and had a number of holes in the sheet as well for heat dissipation, did not really work so I then tried 6mm or 1/4” it still warped slightly though not as bad as the 3mm or 1/8” hence my recommendation saying 8mm or 5/16” would be better.