The AquaFX TFC Membrane Aquarium Filter helps to keep your aquatic pals happy and healthy. This thin film composite， reverse osmosis membrane offers a top-quality performance. The filter operates at pHs from 2 to 12， and can also tolerate a pH of one for short-term use， making it a versatile addition to your tank. It’s non-chlorine tolerant and operates to a maximum temperature of 110 degrees Fahrenheit. Best of all， the membrane fits any standard residential membrane housing， so you can upgrade your existing housing.