Sulfur denitrator users?

[delphinus]

Hmmm weird. No, I definitely get high nitrate readings from my Salifert and Elos test kits. The Elos one is right off the chart (ie the colour is darker than the darkest colour reference, and that's 100ppm). In the case of the Elos, I thought it was nitrite interfering with the nitrate reading that's why I started testing nitrite. I had elected to stop testing nitrate altogether until I would get a zero nitrite level (not realizing that the sulfur was interfering there).

At any rate, since I last posted, my nitrate monitor arrived in the mail. Freshly calibrated I get a reading of 26ppm NO3 in the tank, and 13ppm NO3 reactor effluent. So you were right, it seems it was working after all.

But the two test kits I was using are definitely showing nitrate levels on the high end. In fact, I was ready to give up on the sulfur reactor idea altogether because I thought it just wasn't working. Glad that finally there's an indication that it has function after all.

 

[delphinus]

What are things to watch out for? What are the things that can prevent a sulfur denitrator from functioning properly?

I have been running mine for 6 weeks now and it just doesn't do anything. The nitrate tests slightly less on the output than it does on the input but it never reads zero. I've tried a flowrate as slow as one drop per 5 to 6 seconds, and a flowrate as fast as two drops PER second. Nothing ever changes. In the meantime, the tank nitrates slowly climb.

(I should mention that there is practically a zero bioload! Tank is a 115gallon cube, 60 lbs of rock, 60lbs of sand, ONE FISH, one anemone which I have not fed since December, some cleaner shrimp some peppermint shrimp and some snails. Not exactly a slam dunk here in terms of blaming the bioload for the excessive nitrates.)

Can the sulfur be the problem? Maybe it's low grade sulfur? I'm using Caribsea LSM as the main substrate. It has never produced a sulfurous scent. I mean it smells so bloody clean I think you can drink it. It has ZERO scent. I cannot emphasize this enough: It has NEVER SMELLED BADLY. NEVER! Everyone else I've talked to complains about the rotten egg smell if the unit is too slow. I can't get a scent out of this even if I shut the flowrate down completely for 24 hours. What gives? Shouldn't that be impossible? So I ask this in all seriousness, hoping for some serious discussion: is all sulfur media created equal? Is there any hope in buying a new container?

What else could be wrong? I need this thing to start functioning, I need ideas.

 

[Zephrant]

I've read that some people "seed" their unit with the correct bacteria. I certainly would think that step would be optional, but maybe it is worth a try in your case.

Zeph

 

[delphinus]

Thanks, guess that's worth a shot. Now to find me some ...

 

[klasiksb]

What size is your chamber and how much sulfer do you have in it? What is your recirc. pump? Got any pics?

 

[delphinus]

Here is a picture I've got online of how it is setup. I realize I need to get the unit out of the tight spot it's in and take some more detailed photos to give you a better insight to the details, so bear with me, I'll try to get that later when I'm home from work. But at least this can give you a first impression.

The basic idea is this. It's a converted small calcium reactor. The reaction chamber is 4" diameter. The media height in this chamber is 8.5 inches.

I think the math works out to about 1.75 litres or basically, just under half a gallon. Or basically somewhere around one-third of a container. Of course this is not taking into account the fact that the pump intake comes up a 0.5" PVC pipe up the centre of the reactor.

The recirculation pump is a mag2, the flow through the media is from bottom to top, and it exits the the reactor through the top. From there it goes into the second stage which is just standard calcium reactor media to buffer the effluent before returning to the tank.

One thought I've had is that the mag2 (the recirc pump) is a small pump and maybe I should think about replacing it with a mag5 or mag7. I'm not sure though -- there definitely is flow through the media, you can see the little granules dancing around in there.

The feed to the reactor is a T off the overflow lines (so basically gravity fed), with an irrigation dripline valve inline (ie. the flow control is on the input side of the reactor) which taps into the recirc pump intake.

Please let me know if there's anything I can show in detail, or try to explain better.

 

[kizkiz]

You could try increasing the flow to full for a week or so to get it oxygenated, then start the process from 1 drip per second again.

No other ideas i'm afraid, except to phone a couple of the companies/suppliers of these type of reactors and see what they have to say *just tell em you have their brand)

 

[vic8361]

delphinus,
Could it be possible that the water comming from the overflow is adding air bubbles to the reactor?
I know the water that comes from an overflow often has a lot of air bubbles in it.
Just a thought.

Vic

 

[delphinus]

I can't see any air bubbles but I have to explore every possibility. Is it possible that even though there are no bubbles per se, it's may be that the incoming water has too high an O2 saturation?

I suppose I could try changing the feed situation to a powerhead, or perhaps see about adding 100 feet of 1/4" tubing to the intake to try to have the O2 used up by the time the feed water enters the reactor. I just wish I didn't feel like I was grasping at straws though (i.e. wish there was a way to confirm that this could be the problem). What do you think about adding the 100' of tubing?

 

[cristhiam]

I think 100' is way too long, 75' should be enough. I don't have experience with them but I'm building one with 1/4" OD line, based on this thread http://www.reefcentral.com/forums/showthread.php?s=&threadid=1014664