Sulphur denitrator for large setup

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Hello and welcome. I saw your post on a different thread of mine late the other night and would have responded had it not been so late. Always nice to have international visitors to our site.

You are completely correct in your opinion. I only ran mine on a 120 gallon system with about 1.9 liters of media. I've also only recommended them for low to medium bioload tanks.

When I did run one on a high bioload tank I ran into problems. It could not outpace the accumulating nitrates produced by the tank.

With a system like yours I would definitely recommend a carbon based filter.

Hello and thanks for the response.

With a system like yours I would definitely recommend a carbon based filter.

I would never change a sulfur denitrator for a carbon based reactor. Carbon based reactors can reduce nitrate but can not control the level, biopellets are consumed and have to be dosed carefully. Needs daily attention. And most important, It would not be possible to have control over the nitrate level in the system as I have now using a sulfur denitrator..
VODKA based systems reduce nitrate by accumulation into the bioload but does not remove it. To remove the nitrate, this bioload has to be harvested before it dies.
Carbon based reactors can not remove high bioload at low nitrate levels because they can not handle the flow. There are some polymers on the market which have the need for very high flow to work but nitrate control is not possible using this system. They only can reduce nitrate, not controlling the level.

When I did run one on a high bioload tank I ran into problems. It could not outpace the accumulating nitrates produced by the tank.

A sulfur based denitrator is certainly capable to remove high bioload, even at very low nitrate levels. That is why we use 1% reactors. For a 120gal system we would use 1.2 gal sulfur. Quantity of sulfur is based on the daily to remove quantity of nitrate and the desired level of nitrate on which the reactor has to operate. Because animals grow and multiply the daily to remove quantity is variable. When a production of more than 1ppm daily has to be removed reactors of 2% may be considered when operation at low nitrate levels below 1ppm is desired. To reduce the nitrate level in the system from 1ppm to 0.5ppm the flow must be doubled to remove the same quantity of nitrate daily.
When the reactor is to small for the system one can be encountered by its limits. Most mistakes are made when used as a problem solver to reduce high levels. When the reactor is not big enough at some point the nitrate level will not decent any more because the reactor can only remove the daily production. With the same flow, the reactor is able to remove 2 times more nitrate at 30ppm as when a level of 15 ppm is reached. Flow has to be increased to enter more nitrate. When the reactor is to small it can not handle the increase in oxygen and even less nitrate will be removed. When the flow is mismanaged at that point and decreased to create more anaerobic space, as less nitrate is entered and more anaerobic space is created the system may become anoxic and start to reduce sulfate making H2S. When the flow is reduced more the oxygen reducing bioload will die off and one may conclude a sulfur denitrator does not work. When using a reactor that is big enough all of this is avoided and nitrate levels can be decreased smoothly by increasing the flow to below 1ppm without being encountered by the reactors limits.
This when fluidized bed reactors are used.

What is the max flow your denitrator can handle at the nitrate level it is operating and how much is this level? Any idea of your daily to remove quantity of nitrate?