Finnex HC-810M Digital Aquarium Heater Controller - Precise Temperature Control for Fish Tanks, Saltwater & Freshwater Aquariums - Ideal for Home, Office & Aquatic Pet Stores

Been running this controller for a little over 6 months now with two finnex 300w non-thermostat heaters in my sump for a 125G freshwater tank. This unit has worked flawlessly so far. Love the high/low limit alarm. Comes in handy especially when dialing in your temps. The temp probe lead is a bit short however, the length should be as short as possible for accurate measurement. Also, tanks that require controllers usually run a sump system. My heaters are placed in the return pump chamber and the temp probe is in the chamber immediately upflow. That effectively puts the probe at the furthest point away from the heaters while physically only a few inches from the heaters in the downflow chamber. The lead length is perfect for this kind of setup. I monitor tank temp at either end of the tank, one in the temp probe chamber, and one in the sump chamber. I get no more than .5 degree difference between all the thermometers. This is one of the advantages of running sumps. Just ordered my second controller and a heavy duty splitter for dual 150 Aqueon heaters. Highly recommended and is purpose built for aquarium use in comparison to other controllers on the market that activate heaters and cooling systems.