Does Prime affect denitrifying bacteria cycle?

[robert]

Hi - I've run sulfur denitrators for many years - more than a decade. I also use seachem safe - the powder version of prime liberally. I proactively dose safe if I think anything I do might even has the remotest chance of causing a spike in nutrient availability anywhere in the system.

It can take weeks for a new denitrator to pop - 2 weeks isn't strange - but you should see something soon - I've never seen it take much more. Cloudy water in the top of the denitrator is a good sign that things are progressing.

The only thing I've seen which will cause issues are the use of in-tank antibiotics. In which case I've had to change the media of the denitrator out. Once its running - you can change/refresh media and it will be back on line and working in days as long as you don't clean it too well. Keep some of the older media as "seed" and it will be operating again almost immediately.

When I started with these things - I set them up them like you with the sulfur neatly on the bottom and the coral stone on top. This doesn't seem to work as well as just mixing the sulfur and stone all together. I've also found that only filling the denitrator chamber half way with mixed-up media, leaving 50% of the room for anoxic dead water produces better results.

Cloudiness is good - I bet by the time you read this - you'll have already started to see a drop in nitrates.

 

[SeaDweller]

Hi - I've run sulfur denitrators for many years - more than a decade. I also use seachem safe - the powder version of prime liberally. I proactively dose safe if I think anything I do might even has the remotest chance of causing a spike in nutrient availability anywhere in the system.

It can take weeks for a new denitrator to pop - 2 weeks isn't strange - but you should see something soon - I've never seen it take much more. Cloudy water in the top of the denitrator is a good sign that things are progressing.

The only thing I've seen which will cause issues are the use of in-tank antibiotics. In which case I've had to change the media of the denitrator out. Once its running - you can change/refresh media and it will be back on line and working in days as long as you don't clean it too well. Keep some of the older media as "seed" and it will be operating again almost immediately.

When I started with these things - I set them up them like you with the sulfur neatly on the bottom and the coral stone on top. This doesn't seem to work as well as just mixing the sulfur and stone all together. I've also found that only filling the denitrator chamber half way with mixed-up media, leaving 50% of the room for anoxic dead water produces better results.

Cloudiness is good - I bet by the time you read this - you'll have already started to see a drop in nitrates.

It’s crazy how effective these things are. They seem less complicated than methanol Denitrators too. At one point, my effluent would only read 0.0 ppm NO3 if and only if I kept the effluent at about 3-4 drops per second. You’re right about the “pop” point. Just yesterday i kicked it up to 95 ml/min and I tested this AM and the effluent reads 0.2 ppm NO3, maybe. And tonight it’ll probably be down to 0.0. It’ll be full open bore processing a little more than 4 gph very soon! These things are crazy efficient.

I do wonder if the NO3 is low enough if the bacteria will consume PO4?

 

[jasonrusso]

Hi - I've run sulfur denitrators for many years - more than a decade. I also use seachem safe - the powder version of prime liberally. I proactively dose safe if I think anything I do might even has the remotest chance of causing a spike in nutrient availability anywhere in the system.

It can take weeks for a new denitrator to pop - 2 weeks isn't strange - but you should see something soon - I've never seen it take much more. Cloudy water in the top of the denitrator is a good sign that things are progressing.

The only thing I've seen which will cause issues are the use of in-tank antibiotics. In which case I've had to change the media of the denitrator out. Once its running - you can change/refresh media and it will be back on line and working in days as long as you don't clean it too well. Keep some of the older media as "seed" and it will be operating again almost immediately.

When I started with these things - I set them up them like you with the sulfur neatly on the bottom and the coral stone on top. This doesn't seem to work as well as just mixing the sulfur and stone all together. I've also found that only filling the denitrator chamber half way with mixed-up media, leaving 50% of the room for anoxic dead water produces better results.

Cloudiness is good - I bet by the time you read this - you'll have already started to see a drop in nitrates.

So you think I should remove some of the sulfur if it doesn't start cycling soon?

Does the sulfur start decomposing? Will I see an actual drop in volume in the reactor?

Why would I need to clean it unless it clogs up?

 

[SeaDweller]

Btw Jason, I did begin dosing Dr Tim’s eco balance and Microbacter 7 at the time my NO3 was reading 25 ppm in the tank, and perhaps that helps to speed the process because it was almost weekly I saw the numbers drop. I think for me there were many factors that helped
1) large water changes to get it to a very manageable level
2) introduction of almost 100 acro frags, some small colonies (uptake of NO3)
3) Denitrator finally kicking in
4) dosing bacteria
5) getting my skimmer to run like a top and really efficiently.

I think all of this helped to bring my levels down quickly once I had my target 25 ppm.

I still dose bacteria weekly to keep the biodiversity and to add to it. Perhaps they helped to colonize the media at the same time?

And I’m still feeding 2-3 times a day: flake and pellet in the mornings, sometimes evenings and for sure mysis/plankton/brine at night.

 

[SeaDweller]

So you think I should remove some of the sulfur if it doesn't start cycling soon?

Does the sulfur start decomposing? Will I see an actual drop in volume in the reactor?

Why would I need to clean it unless it clogs up?

The anaerobic bacteria will consume the sulfur if there isn’t sufficient NO3. I’m trying to research if PO4 is consumed.

This is a good quick read:
https://courses.lumenlearning.com/boundless-microbiology/chapter/anaerobic-respiration/

ETA: nope. Doesn’t look like PO4 is utilized in any way.

 

[jasonrusso]

Btw Jason, I did begin dosing Dr Tim’s eco balance and Microbacter 7 at the time my NO3 was reading 25 ppm in the tank, and perhaps that helps to speed the process because it was almost weekly I saw the numbers drop. I think for me there were many factors that helped
1) large water changes to get it to a very manageable level
2) introduction of almost 100 acro frags, some small colonies (uptake of NO3)
3) Denitrator finally kicking in
4) dosing bacteria
5) getting my skimmer to run like a top and really efficiently.

I think all of this helped to bring my levels down quickly once I had my target 25 ppm.

I still dose bacteria weekly to keep the biodiversity and to add to it. Perhaps they helped to colonize the media at the same time?

And I’m still feeding 2-3 times a day: flake and pellet in the mornings, sometimes evenings and for sure mysis/plankton/brine at night.

I have Turbostart 900 sitting on the kitchen table for when I get home. I got that for the weird nitrite levels I was testing.

 

[jasonrusso]

I have Turbostart 900 sitting on the kitchen table for when I get home. I got that for the weird nitrite levels I was testing.

So UPS screwed me. My package was "damaged!!" and I didn't get it today.

I still have a trace of nitrite and my nitrates are reading 50. Effluent still shows nitrates.

I'm not convinced that my nitrates are that high when I am reading nitrites. At this point, I am convinced that AZ-NO3 works somewhat, but I really want to get the nitrites to zero. UPS doesn't want me to.

 

[robert]

So you think I should remove some of the sulfur if it doesn't start cycling soon?
Does the sulfur start decomposing? Will I see an actual drop in volume in the reactor?
Why would I need to clean it unless it clogs up?

I think what you've got will work and should pop sooner rather than later, if its not already working.
Me, personally I would mix 50% sulfur with 50% coral stone (all jumbled together) and fill the reactor only half full. I think they work better like this...but your way works too and looks better. :) Yes, both the sulfur and coral stone slowly disappear into a sludge

I used to run it in layers like you - but I read an Chinese article on waste water treatment using coral-stone and sulfur to remove nitrate and phosphate - tried it their way and liked it better. The exact article is:

Nitrate and phosphate removal in sulphur-coral stone autotrophic denitrification packed-bed reactors"
-Recirculating Aquaculture Engineering Laboratory, Shanghai Ocean University, Shanghai 2009, China

If your curious - check it out.

If your still curious - I can describe a modification that utilizes the denitrator effluent to significantly improve phosphate binding by GFO and precipitate excess iron in the process. Some dose iron in their tanks - but as I have many tangs and feed nori in abundance - eliminating the excess iron helps keep algae in check.

I run a 400gal heavily stocked mixed reef - I used almost no GFO in the past four years.
(I don't actually test for phosphate - It could be through the roof - but my corals do fine - so I'm pretty sure they're not.)

 

[jasonrusso]

If your still curious - I can describe a modification that utilizes the denitrator effluent to significantly improve phosphate binding by GFO and precipitate excess iron in the process. Some dose iron in their tanks - but as I have many tangs and feed nori in abundance - eliminating the excess iron helps keep algae in check.

Of course I am curious!!

Me, personally I would mix 50% sulfur with 50% coral stone (all jumbled together) and fill the reactor only half full. I think they work better like this...but your way works too and looks better.

How long does it last for? When you refill it, you said that if you leave some in there it re-populates quickly and you don't have to cycle it all over again.

 

[robert]

I've never run one out of media before I've refreshed it. I've gone maybe 18 months without adding new media, not because I had to - I just fool with stuff too much.

The lowered pH in the denitrator slowly dissolves the coral stone turning much of it into thick mush releasing calcium into your system. The denitrator also chews through your alk as it works - so you have to test calcium and alk for a while to get used to the new balance.

I posted a DIY Sulfur denitrator thread - a few years ago about the iron/phosphate trick here:
https://www.reef2reef.com/threads/diy-sulphur-denitrator.211365/

Randy and I kinda got off in the weeds a bit - but I try and explain it there...

 

[SeaDweller]

I've never run one out of media before I've refreshed it. I've gone maybe 18 months without adding new media, not because I had to - I just fool with stuff too much.

The lowered pH in the denitrator slowly dissolves the coral stone turning much of it into thick mush releasing calcium into your system. The denitrator also chews through your alk as it works - so you have to test calcium and alk for a while to get used to the new balance.

I posted a DIY Sulfur denitrator thread - a few years ago about the iron/phosphate trick here:
https://www.reef2reef.com/threads/diy-sulphur-denitrator.211365/

Randy and I kinda got off in the weeds a bit - but I try and explain it there...

I’m surprised about PO4 consumption with a denitrator. Have you experienced this yourself? I’m happy if it does occur. My salifert test keeps reading between 0.10-0.25 ppm PO4 when I test, but I don’t have any nuisance algae in my DT, some minor minor GHA in my sump with chaeto, but other than that the brown film algae now takes 3-4 days to develop on my tank walls. Coincidence?

Regardless I try not to chase numbers much at all, except alk.

 

[jasonrusso]

Got this today, hopefully it consumes the nitrite so I get an accurate NO3 reading.

 

[jasonrusso]

It's finally starting to work!! ORP is at -160. Obviously the top is the tank, the bottom is the effluent.

Also, the nitrite in the tank is finally zero. Effluent nitrite has a trace of purple, so the cycle isn't 100% complete.

 

[jasonrusso]

@robert @TitanCi So I came home today and the reactor was very dark and hazy. ORP was at -380. I knew that the effluent line had clogged. I opened the feed a bit to clear the line out and then closed it to the drip-drip again. It smelled like sulfur (expected). ORP was back to -180 in an hour. Did I screw everything up? If the darkening dead bacteria? I really hope not, because it was JUST starting to work.

This is a before and after for comparison.

 

[robert]

Nope - all is good...I should post a picture of mine, you wouldn't worry so much...

You can now run full flow to stall the denitrator and cut it back in anytime you want to. The bacteria is in there and you won't kill it off by opening it up...

 

[jasonrusso]

Nope - all is good...I should post a picture of mine, you wouldn't worry so much...

You can now run full flow to stall the denitrator and cut it back in anytime you want to. The bacteria is in there and you won't kill it off by opening it up...

That's good news!! So you think I can start opening it up? From what I read, you need to wait until the effluent is zero, then open it up a bit, wait until the effluent is zero, and repeat.

Are you saying this isn't accurate? The bacteria will eventually "catch up?"

 

[robert]

Keep it low and let the anaerobic bacteria build up for a bit - then you can do pretty much what you want with the flow...you'll still have regions of anaerobic activity. The slower the flow the larger the regions...the faster, the smaller the regions. Cut the flow and the and the small anaerobic regions will expand very quickly - within hours - because the bacteria will still be there.

I usually run as fast as possible - reading close to zero until I get the nitrate levels in the tank about where I want them - then I adjust faster or slower to maintain it. Don't be too worried - you wont kill the denitrator. The only way I've been able to do that was with antibiotics....and even then I changed the media and it was working full steam within the week.

Clogging is what you'll need to look out for now - I plumbed mine with 1/2" pvc thinking that it could never clog - but eventually it did -

I think you'll need to refresh your coral stone fairly soon - I've settled on 50-50 sulfur/coral all mixed up - as the coral is dissolving and releasing calcium back into the tank.

Have you noticed any change in your alk? You'll probably see a drop which you will probably want to compensate for as this thing ramps up.

 

[SeaDweller]

Awesome! From what I’ve read, once you open it up full flow for an hour or so, all is back to normal regarding the rotten egg smell.

I haven’t had my line clog, but in doing so, for you, you just made it super anaerobic. I think you’re fine and it’s beginning to work as should!

 

[Randy Holmes-Farley]

The anaerobic bacteria will consume the sulfur if there isn’t sufficient NO3. I’m trying to research if PO4 is consumed.

This is a good quick read:
https://courses.lumenlearning.com/boundless-microbiology/chapter/anaerobic-respiration/

ETA: nope. Doesn’t look like PO4 is utilized in any way.

Any bacteria growth utilizes phosphate somehow (inorganic, or from organic molecules). It is one of the main chemicals in a bacteria body.

The simple process of getting energy from the sulfur does not use it, but growth does. :)

 

[SeaDweller]

Any bacteria growth utilizes phosphate somehow (inorganic, or from organic molecules). It is one of the main chemicals in a bacteria body.

The simple process of getting energy from the sulfur does not use it, but growth does. :)

I’m very glad to know that Doc. Thanks! Makes a lot of sense!