Once you have your incubator in a safe place--and you have made certain everyone understands that these are not just inexpensive grocery store eggs that are easily replaced!--you will want to get down to the nitty gritty of incubation. Carefully read the instructions that come with your incubator so you will know how to operate your machine properly. There are many different types of incubators, and depending on the one you have, you will be responsible for varying things when it comes to incubation. Once you have read, re-read, and re-reread the instructions for your incubator, the first thing you should do is get your eggs into the incubator as soon as possible to preserve their freshness, right? Wrong!
Prepare Your Eggs
If you are trying to hatch shipped eggs, they may have been shaken and disturbed during their journey, even if they are perfectly intact and look to be in wonderful condition. (It is for this reason that no one guarantees results with shipped hatching eggs, because there is no way to know if they have been irrevocably scrambled internally during shipping, aside from the fact that it is impossible for a breeder to control the incubation conditions!) It is extremely important to place your hatching eggs large end up in an extra (clean) egg carton and allow their air bubbles to stabilize and move back to their proper places at the large end of the egg. For best results, leave them to stabilize and come to room temperature for about twelve hours, large end up.
Prepare Your Incubator
During this time, you can set up your incubator and get it running at the correct temperature and humidity before your eggs are placed inside. Keep in mind that with the popularly available styrofoam incubators, a tiny, tiny, TINY adjustment can cause a large change in temperature, so it's important to get the temperature right on before your eggs are placed inside. You don't want to put your eggs inside only to accidentally cook them! Even if you are not hatching shipped eggs, it's a good idea to get your incubator to the correct temperature first and to make sure it is running stable before adding your eggs. If you have an automatic incubator, just turn it on and make certain it is functioning correctly before you set your eggs.
Adding the Eggs
When you do add your eggs, the temperature will immediately drop. DO NOT ADJUST THE THERMOSTAT! The temperature will drop not only because you've opened the lid and let the warm air out, but also because you've put eggs inside that may be 20 degrees cooler than the interior of the incubator. It will take your incubator a while to warm them up. If you have a manual incubator and you turn the thermostat up immediately, you can accidentally cook your eggs. Wait several hours--four to six--and if the temperature is still low, make a small adjustment, as small as you can. Then you will want to hover over them to make sure it doesn't get too hot inside. We can't emphasize enough that small adjustments on the manual styrofoam incubators make large changes!
The Importance of a Thermometer and Hygrometer
The styrofoam incubators have manual temperature controls, and it is difficult (and nerve wracking) to get it set exactly right. Small thermometers do come with them to help you monitor and set your incubator temperature, but if those thermometers are off, your incubation can be ruined. With the manual incubators, we usually recommend getting a second thermometer so you can be certain of the conditions inside your incubator. If you don't already have a separate hygrometer, it can also be helpful to get a thermometer/hygrometer combo, since humidity level is so important and the styrofoam versions do not come with a way to check humidity. If humidity is too high, your babies can drown when they try to pip the shell. If it is too low, they can get stuck to the egg membrane: shrink wrapped inside the egg and unable to escape!
Remember, a temperature even one degree off can cause your eggs not to hatch, or it can cause the few chicks that do hatch to be weak and sickly and have other problems. A brief spike or drop in temperature for a few hours is not always problematic, but incubation at the wrong temperature over a long period of time will certainly adversely affect your hatch.
You might also consider a PROBE thermometer/hygrometer. This is a device that measures temperature and humidity remotely: you stick the probe inside your incubator, but the readings appear on the remote unit outside it. A probe can make conditions easier to monitor, but another reason to get a probe thermometer is so that you can better mimic conditions inside your eggs. Here's how you do that: You will need a probe thermometer and a "water wiggler," which is a toy often given out as a party favor at children's parties. You may be able to find one at your local toy store. Put your water wiggler in your incubator with your eggs, and put the probe of your thermometer inside it. You now have a rough way of determining what the internal temperature of your egg is. If you have a power failure, even if the incubator is cool for a while, your water wiggler will be able to estimate for you how the interior temperature of your eggs was affected. if the outage was of short duration, there may have been little effect at all.
You needn't use a water wiggler to incubate, of course. This is just a helpful tip! Using one, though, can be a comfort if the air temperature in your brooder jumps to 104 briefly! Maybe you have misadjusted the temperature, or maybe someone else has done it for you. Regardless, when you use the wiggler method, you will have a good idea as to whether the internal temperature of your eggs is likely to have been affected by the jump in air temperature. Remember, it can take several hours for the temperature of your eggs to rise, so just because there has been a brief mishap doesn't mean everything is lost!
Another helpful tool you can use to help with temperature modulation in the styrofoam incubators is something you may be able to find easy at hand: rocks. Yes, rocks can help you incubate your eggs. I like to add clean, flat rocks to my styrofoam incubator beneath the "floor" of the incubation tray, and within the water reservoir. The rocks absorb and hold heat. Especially when turning your eggs manually, having the rocks in there will help to heat the air up again quickly when you must lift the lid regularly to turn your eggs, because they will serve as low-tech heat sinks. Your eggs won't cool down as much with the addition of rocks used as heat sinks. Make sure they are clean, like everything else that goes into your incubator!
IMPORTANT: If at any time you find a bad odor coming from any of your eggs remove the culprit immediately. If your egg has gone bad, it will never hatch--however, it could explode and contaminate your incubator and all your other eggs!