If the sprouts are still alive, not damping off, the growth is probably benign to them. Looks very wet & much more organic than what I'd try, like sand or loose, unwatered vermiculite *but only for sprouting seeds.* Did you put all of your sprouts in one pot? Some UV rays and circulation, drying out, could help stop that, whatever it is. I'd probably get them out of there. Definitely organic material decomposing in the pot though (so why I think it's benign, the sprouts are alive.) Stuff explodes in nuker & the steam off of dying organic microscopic critters isn't something I'd want in there where I'm going to put food.
