Edited....Found answer in previous post...thanks! Question to folks who have built a styrofoam incubator with a hot water thermostat and 25w bulb... I'm building one to use as a hatcher and am currently using a digital thermometer that's measuring air temperature...I'll purchase a digital with probe for use with a water wiggler tomorrow. My concern is that that the air temps are fluctuating 5-6 degrees with the hot water thermostat...is that normal? Hopefully, the probe will reveal a much more stable temperature in the water wiggler. Thanks for insights from your experiences.