My daughters science fair experiment this year was testing whether washed or unwashed eggs hatch better in her incubator. She got a Hova-Bator 1602N for Christmas. Since her science fair timed perfectly with the excitement of getting the incubator we pulled both projects together. I have told a couple people about this and they seemed interested so I thought I'd share with everyone. We got 24 eggs from a local seller. They were a little dirty but it looked like actual dirt and not animal waste. They were all a day old at the most and she only had 1 rooster so they all have the same dad. My daughter divided them into two groups, one went straight into the incubator and the others were rinsed with a bleach water solution. They were divided up randomly except for one that had a crack, figured just to be safe that one should be in the washed group. It did hatch just fine so it didn't through the numbers off either. Heat and humidity were kept at good levels. we kept the heat between 100 and 100.5 F and the humidity around 50% up until day 18 when it went to 80%. We kept the eggs divided on two sides so the dirty ones wouldn't touch the clean ones and always handled the clean eggs first. The eggs were turned manually 3 times a day at 8 hour intervals and when the eggs were turned we also turned the lid of the incubator so the heating element wouldn't cause discrepencies between the two groups either. It took us a while to figure out how to candle them but we finally figured it out. At day 18 1/2 we candled all the eggs for lockdown. By this time 3 had been removed for not growing. One was from the unwashed side and 2 were from the washed side. They hatched on day 21 and 22. The washed side had only one egg that had started to pipped but died before hatching. Overall 9 out of 12 (75%) hatched. The unwashed eggs had 2 that pipped and died and 3 that just never pipped at all and were thrown out on day 24. Only six of them hatched and 2 of them needed help because they started hatching and then stopped for a long time. The hole was big enough to see them breathing less and less but no change so after 8 hours we intervened. They both had weird toes but we booted them with band-aids and they are fine now. Overall 6 out of 12 (50%) hatched but two wouldn't have without intervention. With these results we will probably wash all of our hatching eggs but would be willing to listen to ideas and input from others. I do have a bachelors degree in a "sort of" science (archaeology) and know that one experiment is definately not definitive. I actually feel really good about the results that we got from the washed eggs for a first hatch. I think keeping the bator by two tropical aquariums probably helped with the temperatue fluctuations other people have had with their hova-bators. The tanks are always 78F and probably stabilize air temps around them. I felt horrible at first about the two chicks that hatched with deformitys, like I was doing terrible animal testing on them, but they look good now. I think we are ready to hatch more expensive chicks now.