Sulfur Denitrification

[nolan_nike]

Does anyone have any long term experience with a sulfur denitrification system?
Opinions?

 

[fmelindy]

bump for this I'd like to know the same. I just disassembled my aqua medic denitrator which works by the standard anaerobic bacteria method (fed by aquamedic's denimar) and was looking at the assembly instructions for the Midwest Aquatic sulfur denitrator. I ordered some of their sulfur media and some ARM reactor media and filled it half and half with room at the bottom and top for the aqua medic recirculation pump to do its job. I've hooked this up to the tank in the last couple of days and will keep everyone posted as to how it goes. Right now its putting out a fair bit of nitrites (which I understand is normal) and the nitrate coming out is thus unmeasurable. The nitrite in the display is still 0.1 (what it was before I hooked the unit up in my sump).

 

[fmelindy]

I've had the denitrator in operation now for 4 days and the effluent from the denitrator is already down to a nitrate reading of 2.5. The display tank nitrates are still at 40 (what they were when I hooked up the denitrator). I have noticed, however, that the pH of the effleuent is low at 7.4 which may cause some problems in the long run. Anybody else notice this with their sulfur denitrators?

 

[sarwiz100]

Google some articles by Randy Holmes-Farley, and google sulfur denitrification. Good articles there.

 

[fmelindy]

Effluent nitrate reading now at 0 and nitrate in tank at 25. All measurements by salifert test kits. Noticed that the ph of the effluent is now up to 7.8. Everything is doing fine in the display tank.

 

[nolan_nike]

Originally Posted by fmelindy
Effluent nitrate reading now at 0 and nitrate in tank at 25. All measurements by salifert test kits. Noticed that the ph of the effluent is now up to 7.8. Everything is doing fine in the display tank.

The PH of my effluent has been around 7.5 Midwest Aquatics is sending me some new calcium media to test that should produce a higher PH. He also suggested that I go with 1/4 sulfur 3/4 calcium in the reactor because of the size of the XL denitrifier in relation to my tank. I've been at zero nitrate in my tank for 5 weeks from 200+.

 

[tony detroit]

Try using some more ARM in the chamber, on top of the sulphur beads. This should bring your pH back up.
Another vote for Sulphur Denitrators. My H & S works very well on my 175gal. Never test for nitrates anymore.

 

[fmelindy]

Originally Posted by Nolan_Nike
The PH of my effluent has been around 7.5 Midwest Aquatics is sending me some new calcium media to test that should produce a higher PH. He also suggested that I go with 1/4 sulfur 3/4 calcium in the reactor because of the size of the XL denitrifier in relation to my tank. I've been at zero nitrate in my tank for 5 weeks from 200+.
Sweet. Hope I get the same results.

 

[fmelindy]

Originally Posted by tony detroit
Try using some more ARM in the chamber, on top of the sulphur beads. This should bring your pH back up.
Another vote for Sulphur Denitrators. My H & S works very well on my 175gal. Never test for nitrates anymore.
I'll try that next time I have to open it up. pH seems to flucuate daily in my adapted unit. Maybe one more thing that could be going against me is that in the Midwest unit the recirculating pump makes the water flow from bottom to top whereas in the aquamedic unit, the recirculating pump makes the water flow from top to bottom. One idea anyway.

 

[nolan_nike]

Last night I removed half of the sulphur and added the new crushed coral/ calcium/ whatever it is from Midwest Aquatics. It is supposed to have a higher PH. They were offering a sample free to current customers. Now I'm about 1/4 sulphur to 3/4 calcium media. I'm going to test the discharge ph tonight to see the effect.

 

[fmelindy]

My modified sulfur denitrator has been up for just about a week now and my nitrates have fallen to between 10 and 25 according to the salifert test kit. Looks like its working!

 

[fmelindy]

Today my nitrate reading was 2.5 by the salifert test kit. The denitrator has been running maintenance-free for almost a month now.

 

[offshore80]

I've had my sulfur denitrator hooked up for about 3 weeks... My nitrates are still smoking at 100ppm at the effluent... I don't get it.

Here is a picture of my unit. It drips into the sump. :help:

 

[offshore80]

better picture

 

[fmelindy]

I can't really see it all that well, what media is that I see in your unit? It dosn't look like sulfur granules....

 

[offshore80]

Here is a better picture.

 

[fmelindy]

oh..... that's definitely enough sulfur granules

 

[fmelindy]

is it possible that your pump is not recirculating? I've seen posts on midwests forums and elsewhere by people who werent getting the expected results and it was that their pump was not recirculating properly and there was no indication that it wasn't functioning properly. Oh, yeah, the midwest aquatic support forums are also really helpful.

 

[offshore80]

With salt prices going up.... weekly 40 gallon changes are going up too. I was hoping to stop those. What a pain.
My main concern was that I had the unit hooked up wrong or something like that. The directions were just a little photo that I couldn't see to well.

 

[fmelindy]

Really? The new instruction manual posted on the midwest aquatic website is actually quite good now as far as setup goes. But the recirculating pump has been the culprit for most people with similar problems, as I understand it.