So some more bad news. Finally got myself some Mephisto seeds. Had my seedlings come up vigorously and grew to about 2 inches then died. I don't over water, the soil is 'moist' at best. My tent humidity is 50%-55% my heat is 76f-78f, pH is 6.4-6.6 - it seems that my environment is dialed in with lots of good ventilation, etc. There is no sign of Damping Off the stems look healthy, leaves are beautiful green no nutes, etc. They just hit 2 inches, look healthy, stop growing, and die.
I started with FFOF soil 3 grows ago. After each grow I re-amend with Gaia Green 444 (1/2 strength) and quality worm castings, let it sit for a month with lots of Mikos etc.
What could be killing my plants? Again, my first 3 grows had zero issues and the conditions were the same. Is reamending soil just a bad idea? In order to eliminate the soil as a culprit I dug out the center of the 5gal pot and put some Promix Seedling Starting organic soil from a new bag, added pumice for aeration, etc. So the same thing is happening in the reused soil AND the new soil.
I should note that this is happening to both photos and autos and from different suppliers.
There has to be something killing my plants it shouldn't be this difficult?