I had horrible pepper seed germination last year - although the peppadew shined amid the sadness
I use the heating mats and all. My house temp is 65-68. Quite a few pepper seeds rotted before ever sprouting.
This year, I bleached them and am amazed at the difference in germination!
Long process but I am loving the results:
Boil water and allow to cool.
Make a tea bag - I used folded over cheese cloth but I know there's a better material. I placed 10 seeds in the center and tied with a string.
Soak this bag in a solution of 1c water and 1/4c bleach, occasionally swirling for 10 minutes.
Rinse in water for 1 minute. Repeat 6 more times with the rinse. I used 7 different rinse glasses.
I am starting over 30 pepper varieties, so this took hours and hours and lots of water.