Don't get a 60 watt day bulb; those are too bright and will hurt a pac's eyes. You should be able to keep your temps up with what you've got. Go buy an infared/digital thermometer; the kind you are talking about can be up to ten degrees off either way.
In your other post, you mentioned leaving half his substrate moist and half dry. Don't do this, just make it uniformly moist; wet enough to clump up but not completely swampy.
Get a more accurate temp reading, and that will help us figure out what else may be going on. I have a hard time believing that 65-70 is accurate with all the equipment you've got. Especially the space heater, those things are great for heating the room.