Advertisement For future reference to know 100% if in pre molt or not (close to molt not just entered premolt) get a flashlight, the stronger the better, wait until it is on the side of the glass (right up against) and shine from underneath it whilst looking form above it. If not in pre molt the legs will be see through, if in heavy pre molt the legs will be almost completely black in most parts. This has worked up until the specimen is around 4.5". At this size I find the legs are a bit too thick to tell with accuracy because it isn't see through qne not in pre molt anymore. That aside, your specimen Seems fine, I wouldn't worry too much. As for temps I keep my males (P.metallica included) slightly below 18C and they are completely fine, so ifit is 18 yours should be okay, it just won't be very active and probably won't eat very often due to a slower metabolism.