Beef shanks --- help! page

[Kilian]

So i've got ~2.5 lbs. of grass-fed beef shanks (bone-in) that have been cooking on low in my crock pot for about 4.5 hours.

How long should I keep them in there?
Should I open up the pot and cut out the bones so the marrow doesn't melt out?

[IvyBlue]

I let them go longer (7 hours on low) only because I always do them while sleeping. I knock the marrow out when done and it's time to make the sauce.