Doesn't hurt to offer. My last feed night first two tubs I pulled open, snakes going blue. I offered anyhow, they both ate. My bee missed the first strike, but went right back at it. Their vision isn't. that great when blue, to judge a strike. As long as its p/k or f/t should be fine. I don't think it can hurt them. They may or may not take it. I guess I would go by their tempermant. I have one female that is just plain grumpy when she is in shed, so I never mess with her.