get a cheap little fan. Personally, if I wasn't 100% sure, I would leave it all in one bator. Don't you have 8 days between hatches? That's plenty of time to have a hatch, move them out, clean it and have another hatch.
I agree with Doug. I would use your one bator that you know is going to hold temp and humidity. The aquarium could work but I bet your hatch rate will be better in the bator.