I got 2 of these and they're extremely inaccurate. The second one was to replace the first upon letting customer service know. Still bad. A 10+ degree difference from both compared to my floating mercury thermometers. The feeling of the water didn't match the digital either. Water would be cold feeling but this would say the temp was 80 degrees or more. Do not recommend. Don't waste your money.

I was looking for a simple, accurate, inexpensive and low profile design digital thermometer. Coralife checked all the boxes. For the first few months I compared the readings to a standard mercury thermometer with no discrepancies. I am confident with its performance.

These are a must-have and you WILL NOT find them cheaper anywhere else, trust me! I went ahead and bought 2 (for each of my tanks), as I saw these in my LFS for $15 - now a quick glance and I know EXACTLY what temperature each tank is- no more guessing or assuming a 5-degree range. I love these, highly recommend!