The issue you have here is that they're underfed. Bioheaven isn't a nutrient so the plants have nothing to feed on other what's in your tap water. Looks like you have a few deficiencies showing all at once.
Hydro needs to be fed from about 7-10 days after germination. I've read other things online, bit I've noticed that if I don't feel after that period and everything else is optimal, I'll start to get the odd twist or yellowing in my leaves. The cotyledons will also yellow prematurely due to the lack of food.
You should also allow the plants to establish a substantial root ball before planting into the system. I would start with a light, single part feed like Formulex 7 days after germination. PH the solution to around 5.5 and keep the EC around 1.2-1.4EC. Why so low on the PH? Because rockwool is alkaline and you need to compensate for that by adding a little more acid.
They will be ready to be transplanted around 3 days after transferring unto the 3" blocks. Once in the system, you can raise the PH to 5.8 and move over to a more complex nutrient like a two-part system, but keep the EC at 1.4EC for a few days to allow them to settle in before raising the EC to 1.7EC. If you make it through that lot, you should have lush green plants that are ready to grow into monsters.
Good luck

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