Heating through plexiglass?

[HanabiraAsashi]

So I ran into a major problem with my smaller tank. My RHP is a half a inch too big to get inside of my tank. I have a piece of plexiglass for the lid of it that was meant for the panel to be bolted to. My options are to, buy a bigger thank (and a bigger piece of plexiglass), buy a smaller RHP (but it would be wasted once this BP is ready for a bigger room). Or buy a CHE.

Question is, Would a t-stat regulated CHE be too hot to use over 1/4" plexiglass with holes drilled in it around the element? The room's ambient temp is 75 so the CHE only needs to get the tank's ambient up 5 degrees.

[Yodawagon]

I would just get the smaller panel.

[Coluber42]

What kind of RHP? I have a Reptile Basics 80w panel on the lid of a 20L. The panel is tapered from the emitting part to the edges, so the emitting part actually does fit inside the tank and the edges sit on the edges of the tank, if that makes sense. I added a few wooden blocks to lift the rest of the lid just a little higher, so now the panel nests very nicely. The lid sits up higher, on the blocks. (It's held on with a luggage strap, because I was too lazy to rig up any more elegant latching system)
An additional benefit is that there's actually a little ventilation most of the way around the edges of the top, so I was able to completely cover the screen. With the ventilation at the sides of the lid instead of on the top, the humidity stays much better.

Sorry if it's hard to describe; I'll try and get a photo tomorrow... but basically, this took me all of 20 minutes to assemble and that counts the time it took to go find the wood.

But basically, the lid is set up on blocks so the panel is higher, and it nests in very nicely. The panel is still low enough that it would stop the snake from being able to slide the lid off if he tried. This setup would NOT work for something like a baby corn snake, which would totally be able to shinny up the corner and squeeze out of the gaps (although even that could be corrected fairly easily if necessary). But not a BP, even a very small baby.