I picked up a free 20 gallon hex tank fixer upper a few days ago. Re-sealed it (removing old silicone first) let it cure for about 40 hours indoors. I just put it outside and filled it up for a leak test. Problem is it is supposed to freeze tonight so I will only be able to leave it out for about 12 hours. If all is well after 12 hours can I call it good since it is a low volume tank? Or should I bring it in for the night and repeat another 12 hour test outside tomorrow if it is warm enough?