Go to home Depot, buy some of that plastic light diffuser and some PVC pipe. Cut the diffuser so that it fits snugly in your egg box, make legs for it out of the PVC, and add water under it. Make sure the water won't come in contatc with the eggs. If you don't want to make the legs, you can stack multiple pieces of the diffuser in there and get the same effect. If your egg box does not have a nice, snug lid, cut a piece of plastic sheeting to fit between the box and the lid. I started using this set up thanks to advice i got here after losing a clutch on vermiculite, and it works pretty well.

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Snakes:
1.1 gray banded kingsnake
1.1 california kingsnake
1.1 kenyan sand boa
1.1 western hognose snake
0.1 albino checkered garter
1.0 florida blue garter
1.1 het anery red sided garter
1.1 reverse oketee corn snake
1.1 blood red corn snake
0.1 amel striped corn
1.0 amel 66% het striped corn
1.1 het albino ball python
1.1 het ghost ball python
0.1 spider ball python
1.0 pastel ball python
1.1 mojave ball python
1.0 butter ball python
0.1 ringer ball python
1.0 African dinker ball python
0.3 normal ball python
1.0 piebald ball python
0.1 het piebald ball python
0.1 Genetic Stripe Ball Python
1.0 Het Genetic Stripe Ball Python
0.1 Mystic Ball Python
Turtles
1-eastern box turtle
2-spotted turtle
2-eastern/midland painted turtle intergrade
1.0-common musk turtle
1-Pink bellied sideneck
6-Northern red belly
Invertebrates
0.1 southern black widow
1-Tanzanian Giant Tailless whipscorpion
Amphibians
0.1 Ornate Horned Frog
Birds:
1.1 red avadavit
2-blue breasted cordon blue
1.1-black cheeked waxbill
0.1-star finch
1.0-Java rice sparrow
2.0-owl finch
1.0-hybrid munia
0.1-White bellied caique
Fish
2-corydoras cats
1-African upside down cat
normal stuff
0.1 black lab