Review on VIVOSUN Aquarium Thermometer Terrarium Temperature Fish & Aquatic Pets by Michael Schafer

I have used them in several of my discus aquariums. I've always used standard glass thermometers, but have found that with larger discus (like any cichlid) my glass thermometers break when they're in mating mode trying to mark and defend their territory by hitting objects. It's hard to explain, but if you know cichlids and their mating behavior, and then look at the size of the disk in relation to thermometers, you'll understand. I needed a solution that couldn't break and this worked!