Very good Martin.
It seems that you're going to solve the "heat" problem. This summer the temperature reached 29 Deg.Cel. in my semi-basement garage & most of my fish, didn't like it at all.
In winter, you need more "heat", as this will fill up the upper part of your fish room first....... at least that's what I think. 
Please treat Corydoras as community inhabitants & not as scavengers.

