Here's how it works:
As tank water is pumped into the reactor, it is laden with all the chemicals inherent within the system including nitrates. Also present is oxygen,(referred to as O-2). Anerobic bacteria cannot survive with even the smallest traces of O-2 and to eliminate this gas from our reactor we have provided all that surface area within the coils for these O-2 munching helpers. As the water works is way down and around the coils, the aerobics strip the water of all O-2 as they convert ammonias into nitrites. The nitrites then enter the center chamber and flow back out into the aquarium. This is why you will test positive for trace nitrites when checking the effluent going back into your tank. In fact, you may experience a higher concentration of nitrites than you have since 1st cycling your system way back when. Don’t be alarmed…this condition is perfectly normal and part of the cycling process of your denitrator.
Slowly, as more and more aerobics inhabit the coils the amounts of available O-2 in the lower portions of the coils will become smaller and smaller. Eventually, all the bacteria in the upper reaches will have depleted the O-2 by the time the water enters the center chamber.
O-2 depleted water now occupies the center section of your chamber. The bio media provides the area for the denitrifying bacteria to gain a foothold and begin to flourish. The amount of nitrate concentrations will ultimately determine the size of this colony once fully established. The colony will expand and contract as the available nitrates fluctuate. Relevant to this project is patience!
The diagrams, along with this article illustrate the main cylinder, the ball valve and pump assemblies. In reality, these are all the components needed to establish a nitrate-removal system on any saltwater application. So, let’s begin:



