Hey man, sounds like you have some experience with coco. So I’m just going to give you my thoughts and you can decide.
I have tried several different ways of starting plants in coco. I won’t go into all of them now, but I’ve done a few. What I’ve found is that feeding right away gets the best results with a coco/perlite mix. For rooted clones I start at an EC of 1.0. For sprouted seeds I start them at an EC of 0.8. I feed just to runoff 3x a day. However, I think the seeds may like 2x a day better. More to come on that later. This is from day one. Coco is not soil and must be approached differently. It should never dry out. Weight of the pot is irrelevant with coco. It should never dry out. Sorry, that is just very important and needs repeating. I know you said you have been using coco with clones for years just fine, but I bet you’ve had some nutrient tip burn and random deficiencies in late flower and wondered where it came from. It is very important to feed coco at least daily.
Just as an example of what I’m advising. I happen to have 3 Strawberries & Cream from Connoisseur genetics going. I put the germinated seeds directly into 1gal pots of Roots Organic brick coco with 30% perlite on Oct 13th. They got
Remo Nutrients veg mix 3x a day once they pushed their first serrated leaves. They are under a 400w MH light. I just took these pictures now.
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