What CHE wattage??

[Whitefang]

My house tends to stay pretty cold, I'm building a new cage for my hog island boa. I will be using a 11x11 ultratherm mat. I also want to supplement with a CHE to help raise the ambient temps in the cage. I am using a 116qtl tub. The CHE will be regulated using an inkbird itc 1000 temp controller.

I'm just unsure of what wattage to buy here. Also I'll have a screen cut out on the top of the lid with a mesh so no worries about the CHE melting the plastic