Carbon and Phosphate Reactors

The Problem:

I currently don't have an elegant way of running Carbon and Phosphate media in the tank. While I would like to have these running 100% of the time, having a filter bag with the media seems a little sloppy.

The Solution:

I purchased two Phosphate reactors from Two Little Fishies, and placed them in-line with the "maintenance T" that I created during my re-plumbing project.

The solution consists of two Phosphate reactors plumbed in-line with the return. The plumbing used is 1/2" plumbing so as not to drive too much flow through these reactors. It is important to gently suspend the Phosphate or Carbon media, but not to create so much turbulance that they disintegrate from colliding with itself.

Unions and ball valves were used unsparingly to facilitate maintenance, as media will need to be frequently replaced. Either chamber can be filled with Phosphate or Carbon media.


Maintenance of the Phosphate reactors from Two Little Fishies can be somewhat cumbersome. There are ten nylon screws that need to be removed whenever the media needs to be serviced. Also, the sponge filter inside the chamber tends to fill with detritus or small pieces of media which can cause the sponge to float. I had to place a piece of PCV pipe inside the top of the chamber to hold the sponge in place. If the sponger filter doesn't provide a barrier, some of the reactor media can return to the sump.

I suspect that one could easily perform a DIY project on this; however, to the credit of Two Little Fishies, they didn't charge a lot of money for the reactor (retail approximate USD $35 ).

Ball Valves and Unions

Filtration Chambers