imo hydroton dosent provide enough moisture to pop a seed but im sure its been done, why not just germinate then place in a small starter cube where you can more easily control the moisture/watering then when its a nice size seedling put in hydroton?? there is really no substitute for doing things rite, i guess if you have some beans you dont really care for you could try it but if paying for some pricey top strain beans i wouldn't try it. i just germinated 5 fem's in paper towel 3 days ago and all popped already and are already sprouting out of my rapid rooters. just my thoughts.