trouble with water wiggler!!!

[Cuqui18]

hi i just built an incubator out of a plastic heavy duty cooler and followed someone elses thing on here (heres link)

so my temp is working and the water heater thermostat keeps it at about 100 degrees BUT...my water wiggler temp is about 90..... what am i doing wrong? i need to start incubating ASAP!!!! but why is the temp like 10 degrees lower in the wiggler? is this ok?

any help s appreciated!!!

 

[Cuqui18]

https://www.backyardchickens.com/web/viewblog.php?id=7562-The_GopherBator

 

[rebelcowboysnb]

It should be the same temp or real close. Has it been in there long enough to warm all the way up?