C.H.E. wattage for dubia colony?

[DawnsNova]

After being unable to maintain proper temps for my dubia colony, I am going to begin using a ceramic heat emitter/dome fixture warm things up.
Of the several wattage/sizes available, which one is correct? I have a 27 gallon rubbermaid bin.
Thanks!

 

[Soulwind]

Mine are kept in the basement and I've had troubles keeping them warm enough too.

Currently, I have a zoo-med UTH under the bin and a 100 watt CHE sitting over the top of the bin.

When I open the lid, I see a huge exodus away from the top of the egg crates, so I know they've been accumulating
up near the top, closer to the CHE's warmth.

However, be careful with a CHE -- I let mine tip down too close to the lid and after a few days came back to
find a big white spot (on a green plastic lid). When I touched it, my finger went right through the lid :roll:
so apparently it got hot enough in that one spot to degrade the plastic.

I have since cut out the area around where the CHE points and covered it with a thin sheet of metal I got at the
hardware store (about 6" bigger on all sides than the CHE's dome and held in place with aluminum tape) so that can
disperse the heat better and more safely than the plastic.