Sulfur Denitrator questions.

[iReefer12]

It’s really interesting, I noticed my ORP slipped into + last couple of weeks, haven’t noticed any change in the parameters of the tank, so I figured it was no big deal. I checked the Effluent yesterday and it was the same as the display NO3… I then turned down the flow rate quite a bit, almost 50%… ORP went down and is now around -50, tested the effluent today and it’s about 1/2 of the display, hoping tomorrow it’s even lower again.

My theory is that when the No3 levels are high, you need a high flow rate to be in a safe but effective range, and as No3 levels drop and lower, you need a slower flow rate to be effective… just an observation and a theory, no idea if it’s accurate?

 

[MikeTheNewbie]

Hi iReefer,

I thought you might be interested in my own sulphur reactor journey. Through excel, I have plotted my ORP readings (ml/min) vs effluent FLOW (mv) from Jul6th to today Aug 8. During this time, my Display tank nitrates have gone from over 75ppm to today 15ppm. Over this period I have adjusted the flow daily, with the goal of keeping my effluent nitrates above 0ppm. This measuring the effluent nitrate and the adjusting the effluent flow was extremely tedious and often I could not adjust the flow correctly and wound up with unwanted zero ppm effluent readings. I believe that 0ppm effluent results in unwanted sulphur gas bubbles collecting at the top of my reactor lid.



I tried my best to find some general relationship of the ORP values to help me with when to adjust the effluent flow and by how much. The ORP values were so sensitive to the flow, sometimes quickly rising way up or sometimes quickly falling way down, that I could not make any general conclusions to when to make flow adjustments and still keeping my effluent nitrates above zero.



Since you have also seemed to be keeping track of the ORP values during your journey, I thought you might be interested in my scattered results. Personally, I have not found any meaningful relationships using ORP to help me dial in the sulphur reactor.

Ron

I love using charts to find trends and correlations. Too bad ORP didn't help dialing in the flow.
How were you measuring flow?
Have you tried comparing ORP against NO3 reading at the effluent?

 

[MikeTheNewbie]

This is the math I accumulated when I was researching to set one up.

————————————————
Volume of media to use:
Math: 0.6L of sulfur per 100 gallons.
800g x 0.6=4.8.
So go with 4l to start. (I erred on the side of caution.)

Flow rate:
Math= 3-4lph per L of media.
4L x 4LPH = 16LPH = 260ml/Min
Flow rate: If 4L of media = 260ml/min

____________________________________

Sorry everything is in liters, but that’s the unit of measure everyone was using, so just went with it.

Did you rinse or prepare your sulfur media before adding it to the reactor?
I noticed some dust on mine, and wonder if rinsing or letting it sit in RODI water for some time would be useful.
Thanks for sharing your experiences!

 

[14 foot reef]

Did you rinse or prepare your sulfur media before adding it to the reactor?
I noticed some dust on mine, and wonder if rinsing or letting it sit in RODI water for some time would be useful.
Thanks for sharing your experiences!

I ran 200ml per hour through mine for a on the fly water change. Ran about 20 gallons total water through it, then dialed down flow to 20 ml per min for 2 days, now the Kamoer doser is set at 4ml per min

I did not notice any yellow dust collect on my pre-filter see photo

 

[14 foot reef]

This is the math I accumulated when I was researching to set one up.

————————————————
Volume of media to use:
Math: 0.6L of sulfur per 100 gallons.
800g x 0.6=4.8.
So go with 4l to start. (I erred on the side of caution.)

Flow rate:
Math= 3-4lph per L of media.
4L x 4LPH = 16LPH = 260ml/Min
Flow rate: If 4L of media = 260ml/min

____________________________________

Sorry everything is in liters, but that’s the unit of measure everyone was using, so just went with it.

@iReefer12

Most everything I read was 1 drip per second of effluent. Mine has only been running 4 days.
I have 1000 gallons of system water
Running Kamoer doser through the large TX-3 AquaMaxx Carx at 4 ml per minute. ( 1 Drip per Second )
By the looks of your formula I should be running .......
5 Liters of media, (which I am.) topped with a floss line 2" thick and then about 7 liters of Reborn on top.
But looks like I need to move my effluent dosing amount to 336 ml per Minute.

Is that correct ?

 

[Rst]

I love using charts to find trends and correlations. Too bad ORP didn't help dialing in the flow.
How were you measuring flow?
Have you tried comparing ORP against NO3 reading at the effluent?

Hi, I measure the effluent flow with a 1 minute timer and a graduated cylinder. My flow are always plotted in units of ml/min. Yes I have also charted ORP (I convert ORP to pH first so that the chart is more readable) to the effluent Nitrate readings.

Here is a graph of all of the measurements during Jul 7 to Aug 9th this year. Over this time I charted 4 parameters. Looking at the chart over time,

the lowest bottom graph is my effluent Nitrate measured in ppm Nitrate showing 2.0ppm on Jul10 and 1.3ppm on Aug10th

the next blue line up from the bottom is the pH values measured inside the Sulphur reactor starting with pH of 9,0 on July8 and ending on Aug10th with a pH of 5.64. NOTE: the pH values are measured can easily be exactly converted to ORP values with the use of a conversion table as shown in the pdf attached. Since the values of ORP has a very large swings of values both positive & negative (ie minus 116 orp at pH of 9.0 to positive 81.2 orp at pH of 5.6, instead for the ease of readability & plotting, I have chosen to plot and show the pH values instead.

the next plot up in red is my measured effluent flow rate over time measured in ml/min. It starts with 29ml/min on July8 and ends with 44.9ml/min on Aug10th.

the last plot is my measured Display Tank Nitrate level measured in ppm. The first point plotted shows 44.5ppm on July 19th and dropping down to 12.9ppm Display Tank Nitrate.

Hope you find this useful,
Ron

 

[MikeTheNewbie]

I ran 200ml per hour through mine for a on the fly water change. Ran about 20 gallons total water through it, then dialed down flow to 20 ml per min for 2 days, now the Kamoer doser is set at 4ml per min

I did not notice any yellow dust collect on my pre-filter see photo

Wow that looks like a serious installation!
Thanks for sharing and for the great idea of flushing some of the initial output /on the fly water change. I'll do the same thing shortly.

 

[MikeTheNewbie]

Hi, I measure the effluent flow with a 1 minute timer and a graduated cylinder. My flow are always plotted in units of ml/min. Yes I have also charted ORP (I convert ORP to pH first so that the chart is more readable) to the effluent Nitrate readings.

Here is a graph of all of the measurements during Jul 7 to Aug 9th this year. Over this time I charted 4 parameters. Looking at the chart over time,

the lowest bottom graph is my effluent Nitrate measured in ppm Nitrate showing 2.0ppm on Jul10 and 1.3ppm on Aug10th

the next blue line up from the bottom is the pH values measured inside the Sulphur reactor starting with pH of 9,0 on July8 and ending on Aug10th with a pH of 5.64. NOTE: the pH values are measured can easily be exactly converted to ORP values with the use of a conversion table as shown in the pdf attached. Since the values of ORP has a very large swings of values both positive & negative (ie minus 116 orp at pH of 9.0 to positive 81.2 orp at pH of 5.6, instead for the ease of readability & plotting, I have chosen to plot and show the pH values instead.

the next plot up in red is my measured effluent flow rate over time measured in ml/min. It starts with 29ml/min on July8 and ends with 44.9ml/min on Aug10th.

the last plot is my measured Display Tank Nitrate level measured in ppm. The first point plotted shows 44.5ppm on July 19th and dropping down to 12.9ppm Display Tank Nitrate.

Hope you find this useful,
Ron

Ron, thank you so much for sharing I'll spend some time digesting your charts and seeing how my system behaves compares to yours.
I have a time series database constantly polling the Apex for data. Unfortunately I don't think the Neptune 1/4 in fluid meter works at these low volumes
I'm planning to use a Kamoer pump so I guess I'll manually track every time I change the flow and after calibrating.
Thanks again for the help!

 

[Rst]

Ron, thank you so much for sharing I'll spend some time digesting your charts and seeing how my system behaves compares to yours.
I have a time series database constantly polling the Apex for data. Unfortunately I don't think the Neptune 1/4 in fluid meter works at these low volumes
I'm planning to use a Kamoer pump so I guess I'll manually track every time I change the flow and after calibrating.
Thanks again for the help!

The 1/4 apex flow meters definitely won't handle these very low flows. What would really be much more useful would be a metered programable Kamoer like pump whereby you could change the flow according to the orp(pH) inside the Sulphur reactor . Unfortunately, no such programable pump currently exists. The only solution is to manually change the flow frequently to meet the ever changing orp(pH) in the reactor.

 

[14 foot reef]

Tested my effluent after 4 days at 4ml per minute. Test is 0.00 Nitrate. Adjusted effluent to 30 ml per minute
Will keep testing and adjusting the effluent higher until I see 3-5 coming from effluent test.

I'm very excited to see this change already. I have faith in this new Sulfur DeNitrater

Tank = 25.9 Effluent = 0.00

 

[Sean Clark]

The 1/4 apex flow meters definitely won't handle these very low flows. What would really be much more useful would be a metered programable Kamoer like pump whereby you could change the flow according to the orp(pH) inside the Sulphur reactor . Unfortunately, no such programable pump currently exists. The only solution is to manually change the flow frequently to meet the ever changing orp(pH) in the reactor.

I use my apex to cycle a versa pump on and off via the ORP inside the reactor. The versa is set to a constant 30ml/min which works perfectly for me. I keep my reactor ORP between -245 and -255.

 

[Rst]

I use my apex to cycle a versa pump on and off via the ORP inside the reactor. The versa is set to a constant 30ml/min which works perfectly for me. I keep my reactor ORP between -245 and -255.

Hi Sean,
I did also think of turning my effluent Kameor flow pump on & off but I didn't (& still don't) understand how the ORP value should be set in order to keep my display tank nitrates within a specific range. In my case I used a table of pH vs ORP values and then monitored the pH equivalent. (see my post #46 with a graph & pH table). Any chance you could describe in more detail how you use your Sulphur reactor together with ORP control and ultimately are able to keep your tank nitrates within your desired range? Also how were you able to determine that the optimal orp range was -245 to -255? The method I have been using is tedious and relies on constantly measuring & adjusting the effluent nitrate and flow to force the effluent nitrate to stay between 2 to 4 ppm.
Thanks, Ron

PS - I am currently making my way thru your incredible build thread. Absolutely facinating!

 

[Sean Clark]

Hi Sean,
I did also think of turning my effluent Kameor flow pump on & off but I didn't (& still don't) understand how the ORP value should be set in order to keep my display tank nitrates within a specific range. In my case I used a table of pH vs ORP values and then monitored the pH equivalent. (see my post #46 with a graph & pH table). Any chance you could describe in more detail how you use your Sulphur reactor together with ORP control and ultimately are able to keep your tank nitrates within your desired range? Also how were you able to determine that the optimal orp range was -245 to -255? The method I have been using is tedious and relies on constantly measuring & adjusting the effluent nitrate and flow to force the effluent nitrate to stay between 2 to 4 ppm.
Thanks, Ron

PS - I am currently making my way thru your incredible build thread. Absolutely facinating!

I tried to find the sweet spot where the flow through the reactor kept the -250 ORP average that I was shooting for. Why -250? Because I read in an article on waste water treatment that the bacteria likes that zone, so I ran with it. It works for me.
I am keeping the reactor anoxic without going stagnant. I use a large amount of sulfur media double or triple what I need for the size of my system. The effluent is always zero nitrate even if I were to run it at 200 mL a minute. The bacteria population manages itself based on the nutrients that it can receive from input.
2 weeks ago my nitrates were 5.9 so I fed a little bit less. I didn't touch the reactor this week. My nitrites are 3.1 I just test regularly and adjust feeding. (I feed very heavy most of the time)
The bacteria colony is limited by how much water you feed it. So for me, 30 ml keeps it in that zone where the bacteria population can ramp up or ramp down quickly to adjust to the current level of nitrate.
I'm not claiming to know everything there is to know about the science behind everything but I've been using a sulfur denitrator for 10 years and it's fantastic when you get it dialed in.

30 ml a minute keeps my system from cycling on and off a lot. I would like it to run continuously and still be negative. 250 millivolts orp. 30 ml per minute gets me very close to that continuous run time on the feed pump.

Thanks for the kudos on my build. I need to give it some updates.

 

[Rst]

I tried to find the sweet spot where the flow through the reactor kept the -250 ORP average that I was shooting for. Why -250? Because I read in an article on waste water treatment that the bacteria likes that zone, so I ran with it. It works for me.
I am keeping the reactor anoxic without going stagnant. I use a large amount of sulfur media double or triple what I need for the size of my system. The effluent is always zero nitrate even if I were to run it at 200 mL a minute. The bacteria population manages itself based on the nutrients that it can receive from input.
2 weeks ago my nitrates were 5.9 so I fed a little bit less. I didn't touch the reactor this week. My nitrites are 3.1 I just test regularly and adjust feeding. (I feed very heavy most of the time)
The bacteria colony is limited by how much water you feed it. So for me, 30 ml keeps it in that zone where the bacteria population can ramp up or ramp down quickly to adjust to the current level of nitrate.
I'm not claiming to know everything there is to know about the science behind everything but I've been using a sulfur denitrator for 10 years and it's fantastic when you get it dialed in.

30 ml a minute keeps my system from cycling on and off a lot. I would like it to run continuously and still be negative. 250 millivolts orp. 30 ml per minute gets me very close to that continuous run time on the feed pump.

Thanks for the kudos on my build. I need to give it some updates.

SUPER HELPFUL. I will start experimenting using your advice. Thanks, Ron

 

[MikeTheNewbie]

I use my apex to cycle a versa pump on and off via the ORP inside the reactor. The versa is set to a constant 30ml/min which works perfectly for me. I keep my reactor ORP between -245 and -255.

Hi I keep reading that I should avoid letting ORP go below -300 mV or I'll start generating hydrogen sulfude.
My Apex has always shown positive values and right now it is showing 217.
It is only been 2 days since I started the reactor.
Should I expect to see the value in the Apex dashboard transition to negative as bacteria starts doing its job?
Thanks

 

[MikeTheNewbie]

Tested my effluent after 4 days at 4ml per minute. Test is 0.00 Nitrate. Adjusted effluent to 30 ml per minute
Will keep testing and adjusting the effluent higher until I see 3-5 coming from effluent test.

I'm very excited to see this change already. I have faith in this new Sulfur DeNitrater

Tank = 25.9 Effluent = 0.00

Got to love those Hold button reminders
I'm with you, it is confusing with the calcium egg checker that turns off if you hold the button.

 

[14 foot reef]

Hi I keep reading that I should avoid letting ORP go below -300 mV or I'll start generating hydrogen sulfude.
My Apex has always shown positive values and right now it is showing 217.
It is only been 2 days since I started the reactor.
Should I expect to see the value in the Apex dashboard transition to negative as bacteria starts doing its job?
Thanks

Just trying to be helpful as I'm not sure where your probe is, but, you have to move the ORP probe to the reactor. That's where you measure the negative ORP - Not in the system. You may know that though.

 

[MikeTheNewbie]

Just trying to be helpful as I'm not sure where your probe is, but, you have to move the ORP probe to the reactor. That's where you measure the negative ORP - Not in the system. You may know that though.

Yeah it used to measure 250-270 when it was in the tank although I never paid attention to it. Now that it is in the reactor I the measurement is around 217-220.
It hasn't moved much. I wonder if it will actually start going down to negative values at some point or if the sign won't change.

 

[14 foot reef]

Yeah it used to measure 250-270 when it was in the tank although I never paid attention to it. Now that it is in the reactor I the measurement is around 217-220.
It hasn't moved much. I wonder if it will actually start going down to negative values at some point or if the sign won't change.

OK, perfect. 2 Days in you wont see a drop in ORP
what is your ml per minute on effluent ?

 

[Sean Clark]

Hi I keep reading that I should avoid letting ORP go below -300 mV or I'll start generating hydrogen sulfude.
My Apex has always shown positive values and right now it is showing 217.
It is only been 2 days since I started the reactor.
Should I expect to see the value in the Apex dashboard transition to negative as bacteria starts doing its job?
Thanks

Correct, if your water is too stagnant the ORP will drop too low and the reactor will start to produce hydrogen sulfide and smell like rotten eggs. You don't want that to happen. If it does happen, it's not the end of the world. Just turn the flow up to raise the ORP.
Apex does not report negative orp values. It'll drop to zero and then stay at zero. Even when it's negative. You have to reverse the polarity on the orp probe to get a negative number but you also have to remember it's going to look like a positive number. I have a whole write up on this on apex form here My negative orp for Apex instructions.
Your numbers are likely correct and will keep falling but you will need to reverse the polarity to keep going down this rabbit hole.