Grrr. My biopellet reactor died

[Reef Pilot]

Never could get why the circulating, when these reactors first came out. Bought my Vertex UF20 several years ago and has been totally hassle free ever since. I have it T'ed off my return pump and it has a ball valve on the input that allows easy control of the tumbling. Only maintenance was topping up pellets every few months. I have had as much as 1000 ml bio pellets running in it. Never requires cleaning or maintenance. But with zero nitrates for so long now, my bio pellet reduction has drastically slowed, so haven't touched mine now since Nov/2012, and still has about 1/2 cup tumbling in the bottom.