ETI Aquarium Thermometer LCD Digital Thermometer with Suction Cup Fish Tank Water and Room Temperature Thermometer for Fish Tank Aquarium

Works well and appears to be accurate. I. Pleased with my purchase and would probably buy again.

Small, accurate, well made and well priced, this thermometer runs off an AAA battery that lasts for well over a year. The water probe can be fixed to the inside of the aquarium with a special suction cup (a nice addition that many other designs do not have) and the display can show either the water temperature in the tank or air temperature outside. It records both maximum and minimum temperatures and an alarm can be set to sound when a certain temperature is reached. All this in a module about the size of a matchbox.One word of warning: if you use it in a marine tank that has an ozone generator attached, do NOT place the thermometer probe anywhere near the airflow in the water as the display will go crazy flicking between different temperatures. No idea why, it just does.This is an excellent piece of kit that I recommend without hesitation.

I find this thermometer very accurate and easy to set up. I have bought several before and all of them are way out. I like this one as its easy to set up the alarm. You set it to what you want and it let's you know when things are not right.

Having read reviews on several of this type of aquarium thermometer the general opinion seems to be that none are particularly accurate. This unit seemed to buck the trend and so I decided to buy it. All I can say is I have three thermometers in the tank - a traditional mercury style, this one and a heater with a built in readout and they all read the same (albeit this one to the extra decimal place) and so can only assume that it/they are accurate. The alarm function is an added bonus that works well and so unit definitely seems to be worth the money .

Simple to operate.Clear display in a small size.Nice features.

What a great little product, accurate enough, the alarm feature is very helpful and upper and lower set points easily adjusted to your needs, but would be better if the alarm repeated periodically (every 10 / 30 / 60 mins as, if you’re not around when the alarm sounds, you’re back to having to notice the issue visually.Haven’t used the suction cup as have inserted probe in to suction section of the filter assembly.

This was recommended on an internet search I did. Really pleased, it gives an accurate reading, very discreet in the tank. Good value for money compared to others recommended on the list. I would buy again. I have a marine tank so have to be very careful of the temperature of the water & this does the job well!

I was impressed at the start. It was more accurate than the usual glass aquarium thermometers. Have 4 and they all vary by 3 degrees. This matched my heater by 1 degree. Checked with an accurate electrical thermometer probe. Was 0.5 degree out. So was happy. But then within a few days I kept finding the probe floating. Cleaned the glass and reapplied each time. Then on my water change day I could have a proper look. The suction pad has just gone soft. It won't hold its shape to get suction. Deeming it useless so forced to return. If you can use without the suction cap it's quite a good accurate thermometer. But if you want it to stay in place on the glass, avoid.