We had 4 mana pools emptied out over night a while back and never could seem to get them refilled. Then this morning I find someone dropping in a empty mana tablets in a pool sucking in what remained in it. Protection does not protect mana pools from dropped mana tablets. so I recommend putting them in enclosed areas.
It appears there are many other unlocked items that some playes will avail themselves of. Crafting signs that use attached storage, Jumping on farmland to get seeds and crop. so looks like a roof is a required and no auto opening doors are required to secure a base.
Crops are protected with the next restart. For the mana pool change the mode to accepting instead of sparing.