my very first clutch, I used perlite very very wet and the light grid. 6 qt sterlite tub with lid that came with the tub with no holes. my eggs dented shortly after I placed them in the incubator. by the time the were ready to hatch. the top was almost touching the bottom. the eggs hatched and it was a weak clutch. talk to a breeder I know that been breeding for years and he told me to use glad press n seal. haven't had a problem since. that was 07
I see post that some do put a small hole in and have good results. I also seen some that has problems also. I recommend the glad press n seal. you can also put the lid on over it. the perfect condition for an egg is 100% humidity without the egg getting wet.