Soil temperature, heat mat

Hi all,

Since I am using a heat mat my plants, which are in week 8 of vegging, are losing green color on its leaves and grow is slower.

I measured the soil temperature and it reached 40°C.
This seems too high.

Has someone experience with this.

Additional info about my setup can be found under another thread : yellowing veins since 1 week under LED

Greet

Heat mats
are they clones
and i dont see y use heat mats at8weeks?

No they are not clones.
I use the mats to generate more heat because the tent is in the basement where it is 14°C and I use a 90W UFO led and 3 20W cfls.