trouble germinating lowryder2

I just got my order in from dr. chronic, of 10 lowryder 2 seeds, they arived 1 week from order so i was excited about that. A couple of seeds were very tiny so i wasn't stoked about that but anyway, I placed the seeds in a glass of water til they sank and then into some rockwool cubes that had been soaking overnight. My problem is that is was a week ago, it has been 7 days since placing them in the rockwool.. I got a little on edge and decided to crack open the cubes and see what was going on with my seeds. out of the ten seeds only one had cracked open. should i continue to wait it out??? has anyone else had problems with seeds taking more than a week to crack open???

seeds must have a steady temp of 21c not any lower. if the temp goes lower than this you will have problems. this is when everybody starts blaming seed companys saying your seeds are s*it. get the temp right and percavere with the seeds for a couple of days to see if you can get a sprout or two.