About three days at constant 30C = 86F. This is about as fast as cantaloupe will germinate. I've gotten them up in as little as 72 hours outdoors but usually it's 4-10 days.

I agree, and just make sure you use a thermometer if you're using any kind of heat. I've ended up with steamed seeds before. Temp's are hard to judge by touch.

So far all my seeds have sprouted except for my cantaloupe seeds which I started 6 days ago at room temp around 68-70 degres.

You probably want to increase the temperature. Taken from www.ehow.com:

"Cantaloupe seeds will not germinate below 60 degrees Fahrenheit. Plants will begin to emerge at about 10 days when the soil temperature is 70 F. Germination time improves as soil temperature increases, peaking at about three to five days when the soil temperature is 90 F, according to Cornell University"

http://tomclothier.hort.net/page11.html

Much too cold for cantaloupe. It is not parsley or lettuce. At least 77F, according to link. There is a whole group of summer veggies that prefer 86F, and will just not cooperate at 68. Eggplant is the most notorious one, but I am told that triploid melons are yet another degree of difficulty beyond eggplants. I usually run two different shifts in the ice chest where the coffee filters are. One at 86 with a sleeping bag covering the chest, and one at 70 or so, no sleeping bag, lid ajar. I use a fluorescent 13W lamp for heat.

I stuck the seeds on top of my cable box where it warm but not hot. Is it normal for the seeds to split open with no root sticking out, cause since I stuck the seeds on my cable box some of the seeds are starting to split apart at the tips.