Extremely useful Heater with external temperature control which is very effective for me to change the temperature. As of now all of my heaters procured during last 15 years were having internal control of temp : you need to take out the heater & set it to a desired temperature. With external temperature control the task becomes easier. Also, the heating rod is made of quartz, extremely hard & explosion proof. Thanks to Indiefur to bring this product in catalog. A must buy for all fish lovers.
