How long to set up my Nitrate Reactor

Answer:

As you are trying to create anaerobic conditions (filter devoid of oxygen) for anaerobic bacteria to grow this will usually take longer than six weeks as the filter will have to go through the normal maturing period as any other biological filter goes through and this can take 4-5 weeks alone. 

Once you have reached this stage then the filter will begin to work and there are several ways to speed up denitrification within the unit. Initially these bacteria in the filter use oxygen but once the oxygen level drops they start to use nitrate. It is important to have a constant steady feed of water to the unit, and most people would use a tee off from the sump return pump. 

If this is the chosen set up then it is important that a shut off valve/tap is fitted above the tee piece and slightly closed down to create some back pressure.  If this is not done then water will always take the easiest route which is back up the larger return pipe and not the smaller feed pipe to the unit.  This then gives an inconsistant supply to the filter which then does not allow for a steady drip rate from the unit and back into the sump.   Also it is advisable to have a long length of feed pipe from the tee to the nitrate filter as usually sump water is laden with oxygen due to skimmers etc and with a short pipe to the filter you can end up putting oxygen into the nitrate filter.  Get a long length of hose/airline etc and coil it up so that the water travelling to the nitrate filter has a long way to go.  By the time it gets to the nitrate filter the oxygen is usually depleted.  

Regarding the drip rate, if you don't like the orange tap then you can always use a G clamp that is used for regulating airflow from airpumps.  These can give a little more control with a drip rate and are freely available from most aquatic shops.  

It has now been found that the unit runs much better if the temperature is run at approx 80 degrees.  The bacteria will grow much faster at this temperature.  Due to the slow flow through the unit the water can cool off (especially in winter) and this will slow the growth of the anaerobic bacteria down somewhat.  It would be a good thing to check the temperature inside the filter.  You can buy a flat heater that is perfect for the nitrate filter, but you may have to ask around to find one.  Do not worry about overheating the tank water as the drip rate is so slow and the water is cooled as it drops back into the sump.  

It is paramount that the bacteria get the methanol food and this must be replaced as stated in the instructions.  Usually as the nitrate falls and the drip rate is increased the bacteria will demand more food.    Set the drip rate at approx 1 drip every three seconds and let it run for several days.  Measure the nitrate and once the nitrate is zero leaving the filter then increase the drip rate to 1 drop every 2 seconds and again run like this until monitoring the nitrate again.  You may find that the nitrate increases slightly, so leave it running at 1 drip per 2 seconds until it falls again to zero.  Then you can step up the drip rate again to 1 drip per second.  This may take days or several weeks and is a little trial and error, but the unit will work in time.  

If there is too much water flow through the filter or not enough food then nitrate will still be present and incomplete denitrification will occur.  

Please note if you get a smell like rotten eggs (this is hydrogen sulfide) then you will have to slightly increase the water flow through the unit until it disappears. Hydrogen sulfide can be toxic so be careful.  

Copper within the system will prevent the growth of bacteria within the nitrate filter.  Some people run a background level of copper especially in fish only systems but Deltec do not recommend using copper with methanol nitrate filters.  

The Deltec nitrate filters have been around for over 20 years and have been sold in many countries.  The methanol method has been tried and tested in many formats and we sell many units and even though Deltec has now changed the design of the filter the method of operation is the same. 

In time you will become to understand how the unit works and be able to get the best from it.   There is not a single man made nitrate filter on the market that you can simply plug in and several weeks later no nitrate.  Each one has to be set up and adjusted accordingly to the system. Unfortunately they do take time to mature but when they are fully mature and working they can be a great piece of equipment.