Have you tried lightly misting the seed covers? It softens them up and many will then fall off or can be easily removed. Using a needle inserted in the seed split to lightly prick them off often works too and if all else fails, small sharp scissors can snip the tips. As long as the majority of the cotyledons remain the plant will do fine.

But it is quite unusual to have this be a chronic or numerous problem, so I would suspect another contributing factor. Using both perlite and vermiculite makes for a very dry mix so it is possible that the seed coat isn't getting the moisture it needs from the mix as the embryo emerges. I would eliminate 1 of them if it was me. Misting the top of the soil at the first sign of emergence might help eliminate some of the problem.

Good luck.

Dave

I have a question...are you removing the clear dome BEFORE the cotyledons are free from the seed coats? Stuck seed coats usually result from lowered moisture/humidity around the emerging seedling. If you are removing the plastic dome or are opening up the chamber before the seedcoats are off, you are essentially reducing the humidity necessary to keep that seedcoat moist. There is a way to make a higher chamber to lock in moisture if your seedlings need some more height before the seedcoat is shed. Also, if your seeds are crushed against the top dome before the shed, that physical barrier can lock the seedcoat onto the cotyledon. Moisture helps to ensure that the seedcoat stays pliable to shed off, as Dave pointed out. The last thing you want to do is try to manually prick off the seedcoat, as you can tranfer tomato mosaic virus to your seedlings, as well as other pathogens.

Try planting your seeds deeper. An extra 1/4 to 1/2 inch will help remove the covers before they emerge.

HTH,
Jeanne

Thanks digdirt, tuscanseed and jeanne re feedback on seeds losing seed covers. Appreciate your assistance. Jeanne, you hit the nail on the head with planting depth. I replanted at approx. 3/8 to 1/2 and all seedllings have lost the covers. Fortunately, I have a wife with infinite patience who removed most of the clinging seed covers by hand and most of the plants look like they'll make it. On the down side, I now have enough seedlings to supply half of Michigan.