I have recently discovered something very important regarding these machines. Although they are pretty perfect to me, I recently struggled with not being able to raise the humity up the last 3 days. I live in Northeast Colorado, which is VERY dry. I have three of these bators(because they are darn near foolproof) and here is what happened. One of the bators was on day 18. I disconnected the turner at the top of the dome and turned the bottle to add the water. I for the life of me could NOT get the humidity about 60% I tried and tried and tried and even enlisted a friend with years of experience with these machines. I had all the water trays at the bottom so full I had water coming out of the bottom! I added bowls of water and sponges on top of that....something was VERY wrong. We were both stumped. I checke d and compared all three bators for minor inaccuracies, and triple checked agains spirit and mercury thermometers for temp and humidity. Nothing. My eggs were so dried out few hatched and those that did didnt live long. It was a long 3 days!! At this point I was sure I would have to get rid of the bator at some point. On to bator #2...now day 18 for it.... I checked the humidity...62%..I unplugged the turner on the top...within 15 seconds after doing that, the humidity dropped to 60%. I plugged it back in...raised back to 62%. I did this 3 times, and had my husband verify I wasnt losing it. He grabbed and incense stick and blew it out and held the stick above the plug in for the turner at the top of the dome. Sure enough, the smoke got sucked into the bator! Which mean the dry climate I am in was being sucked into the bator through that outlet, and the bator couldnt compensate for the dryness no matter how much water I added. After learning this, I kept the turner plugged in and just disconnect the turning arm from the side of the dome. You could also buy one of those child saftey outlet covers they sell or just cover with tape but it works!! I have not had a problem since. I would have just thought this was a fluke, but just got an e-mail from a friend who was experiencing the same problems with hers and when I told her all this she tried it and whoola!! It worked and her humidity started climbing!! No one should have to go through this anymore LOL>...I lost many silkies in that hatch.