katiekelsey
Aquarium Advice Freak
The suction cup on my thermometer worked fine for over a year and now it won't stick to the inside of the tank. It sticks for a few hours then comes off. Anyone know why?
Try soaking it in vinegar for a few min and make sure the glass is super clean where you are trying to stick it. My heater suction does it from time to time.
Might be time to shell out that extra dollar or so.