We feed our Russians a little bit everyday, but how long can a tortoise go without food? We are going to be gone for 5 days at a time on three separate occasions this summer. Would it be all right to give our tortoises a little more food on Day 1 and then leave them without food four another 4 days (making sure our home stayed a comfortable temperature), or would we need to hand them over to a tortoise-sitter while we're gone?