various spots on upper and some middle leaves

Bunch of seedlings going, around 15.. ALl in soil, over the past day or two this came about out of nowhere.. Plants are 25 days or so from seed, upper leaves have these spots and some deforming.

I have had some gnats this year, but its under control, using a organic super soil ive alwways had sucesss with and this is among 3 different strains, eventhough some stronger plants are not showing any symptoms, but most are

Hoping someone can guide me to what they think it may be?

THanks!

Overnight progression pics

Those leaves look puffy, suggesting possible over watering

I see potassium excess. How fresh is this supersoil?