Do I remove the shell husk

It will come off naturally, no need to do anything, they have been doing it themselves for ever. There is a risk of causing damage to the embryonic seedling if trying to interfere. Also, those small cups are totally inadequate for seedling growth beyond a few days by the way, especially if only half full. Black plastic pots about 4 inches across and 5 inches deep are far superior and big enough for 2-3 weeks of growth. Your poor seedlings' roots will hit the bottom of that little cup within 2-3 days, stunting growth. I really have no idea why so many people want to grow massive plants, then start them in tiny thimbles! The first few days/couple of weeks are so important to get a good root system happening, which can not be accommodated/accomplished in tiny coffee cups. Anyway, the husk will come off by itself, no need to worry. Cheers, Organoman.