Review on 🐠 Fluval In-Line UVC Clarifier for Enhanced Aquarium Filter Performance by Sheila Gray

You'd think Fluval designed this cool built-in UV filter for use in the top FX range, but no! Due to the size of the 5/8" hose, it fits models with the smaller 207, 307 and 407 canisters. I had an old 404 in the box and was trying to set it up to run water through the built in UV filter , but that filter leaks and makes noise - the reason I switched to the FX4 about two years ago is a much better design for a larger tank.