Review on Pymeter Digital Temperature Controller: Dual Probe Reptile Thermostat for Heat Mat, Cooling & Heating Pad - Ideal for Reptiles, Homebrew, Aquariums, Greenhouses, Terrariums, and Carboys by Dakota Afzalian

I'm always reading guides and I think I have a good grasp of how things work. Still, I set it wrong at the beginning. Even when I knew it wasn't working properly, I couldn't figure out why. Actually, I thought it was either defective or just not doing what I wanted it to do. I couldn't figure out how to contact the seller without resorting to "ask questions" but I really didn't know what/how to ask. I tried contacting the seller and after chatting with the Revain chatbot for a few minutes I found I was not getting anything and ordered a replacement to test my theory that it was defective. It worked just like the other one, so I spent some time alone with Pymeter and 2 cups of water (1 hot and 1 cold). It took about 15 minutes to get a good idea of it. Intuitively, I would expect each outlet's on/off settings to control the window of time when the outlet is on. That does not work. It actually works smarter and offers more control than a typical home thermostat where you simply set a desired temperature. remain off (presumably cooling) until temperature is reached in the ON setting. The ON temperature should be lower than the OFF temperature. For cooler/fan control: The socket remains off until the ON temperature is reached, after which it turns on. It will stay on (hopefully cooling down) until it reaches the OFF temperature. The ON temperature should be higher than the OFF temperature. In hindsight it makes sense that they called the settings On/Off instead of Hi/Low, I use that in a Betta aquarium. I bought this model because there is no air conditioning in our house. It can be too hot during the day and too cold at night. Here are the actual numbers I'm using: I've connected a heater to outlet 1 and a fan to outlet 2. The ideal betta temperature is 79°F, so I set it: Heater ON at 78°F, OFF at 80°F. Fan ON at 81°F, OFF at 79°F. With these settings, the fan should turn off on a hot day (at 24 C). °) before the heating switches on again at 78°. This prevents heating/cooling from fighting each other. On a cold day the heater shuts off at 80°, so I never expect the fan to start. Further information on usability and the overall product: Pro: *) The alarm function is excellent. I set the alarm to reasonable levels and it warned me it wasn't working as I expected. Unfortunately, this happened late at night. The woman asked if she should start expecting this as a normal occurrence 🤦. The alarm sounds the same as when the settings are changed.*) The packaging is compact/efficient/recyclable*) Conveniently, there is a temperature difference alarm. They mention that if the sensor fails you can use this to find out before it does any damage in any other way. In practice, I wonder if this actually happens. Mehs: *) The block/wires are all white which is quite noticeable in my tank with a black background (see photo). I want everything to be black or at least be able to be replaced with black wires. Over time I will try to hide the cables better in the tank.*) The cables are quite thick. I don't understand why they need to be so thick other than to protect them from extreme temperatures? In any event, they become more of a nuisance in an aquarium.*) As other reviewers have noted, the UI switches fairly quickly, so you'll need to get used to it before you're really comfortable making changes.*) The sensors' calibration was on a few degrees when they arrived. It's good that you can calibrate it, but it was also a bit annoying. I think it's best to put them next to another thermometer that you trust and then adjust the offsets until they match.