Passive denitrator system!

[Iván Olalla]

It's an experiment...but already have great results...we can dial nitrate in the tank by increasing or decreasing media in the cartridges...that along with putting or taking off cartridges in the tray... So far we can dial a nitrate range of about 3ppm to 20 ppm nitrate in our 40 gallon frag tank system.
The idea behind this is to create anoxic zones with bacteria living in a certain amount of media inside cartridges that are water fed passively in a sump system.

So far great results with a fairly new frag tank heavily fed with coral food and only a lawnmower blennie as the sole inhabitant.

Sorry for the broken English, not native speaker here, will post updates, but so far great results!

The idea behind this is to regulate flow trough the media, creating zones for denitrifiyng bacteria and being able to regulate its biomass via media volume and waterflow.

Long therm results are unknown yet, we swap frags with new ones with the same original size of the "control" ones in order to decrease variables, we feed the same amount of coral food and looking for a way to measure nitrogen gas coming out of the reactors in order for comparison of nitrogen output from the sump with and without reactors.

Kind regards!

 

[Iván Olalla]

Baseline: stable nutrient levels with chaeto refugium and skimmer, after that we implemented the passive reactors, same amount of corals and food in the tank, small frags and just a few in order to avoid false positives of denitrification due to nutrient consumption by the corals growth.

Chaeto has not grown or has been pruned during the test and remained almost the same size and weight.

Also phosphate is stable in the .02 and .04 range

Duration of the experiment: 4 months once we got stable nutrient measurements with only chaeto and skimmer, no water changes.

Frag swap once per month

Nitrate levels obtained:

3 cartridges= 2/4 ppm nitrate range
2 cartridges= 7/11 ppm nitrate range
1 cartridge= 15/20 ppm nitrate range

Media used in the passive reactors: Seachem Matrix and Seachem Denitrate in different quantities

 

[Iván Olalla]

Passive reactors

 

[Randy Holmes-Farley Verified Community Expert]

Sounds like a fine plan, especially for folks who like to tinker with things a lot.

 

[taricha]

Very cool. Interested to follow.

looking for a way to measure nitrogen gas coming out of the reactors in order for comparison of nitrogen output from the sump with and without reactors

likely impossible since the denitrified N will be such a small amount compared to the ambient N2 in air and dissolved in water all around.
Probably better to quantify by just holding NO3 spiked water in the sump chamber (while maintaining water circulation in the chamber) for some hours, and measure NO3 decrease directly.
Can do with/without the canisters to make the effect clearer.

 

[Iván Olalla]

Very cool. Interested to follow.

likely impossible since the denitrified N will be such a small amount compared to the ambient N2 in air and dissolved in water all around.
Probably better to quantify by just holding NO3 spiked water in the sump chamber (while maintaining water circulation in the chamber) for some hours, and measure NO3 decrease directly.
Can do with/without the canisters to make the effect clearer.

Tks for your kind words! I like the idea, also we´re thinking of using a destilator with control samples

 

[Iván Olalla]

Here's a pic of the tray and cartdriges...the height of the vent output is elevated from the laminar flow in the fuge, the cartdrige itself can be rotated from 45 to a 90 degree angle against the flow and it has a sleeve that blocks some part of the fuge's lights to avoid algae growth inside of it.

Currently working in a double sleeve that acts as a flow restrictor in order to make easier adjustments

 

[Cory]

I see some tubes in the bottom that look like porus media like marinepure. Are you using them too or just the reactors for this?

 

[Iván Olalla]

I see some tubes in the bottom that look like porus media like marinepure. Are you using them too or just the reactors for this?

Hi Cory good day, yes those are media, we cycled the tank with a certain amount of media and waited for stability in nutrient values prior to use the reactors using the same routines: heavy feeding, chaeto prunning and dry skimming. Once we got very low swings in these values we put in the reactors to observe if there was improvement in the last part of the nitrogen cycle.