A 7 month old who is in good shape can go 2 weeks without a problem so no need to panic just yet
If you are worried about dehydration you can try putting his head to the water or even soaking in 1/2 inch of water in a container with a lid. Soaking can also help with a shed if he is about to. If I have someone who is blue or going into/coming out of blue, I will try to feed if I have their meal thawed before I notice. So, I would just keep trying to feed him on his normal schedule and try the water tricks if you are worried but I wouldnt be too concerned just yet
Good luck with your baby