Description The Aqua One Glass Thermometers are a must-have accessory for any aquarium. Every fish species has specific temperature requirements, so keep an eye on your aquarium with an accurate glass thermometer. The easy to read thermometers include a high-quality silicon suction cup to fasten it in the aquarium. Both models are mercury free for added safety. Easy to read High-quality silicone suction cap Temperature range of 0-500 Does not contain mercury SKU: 152512000004 152512000004