[Okayamapiper]

I've been toying with the idea for a sulfur denitrator, but have been dragging my feet as was trying to scrape together enough pennies for some CaribSea LSM. Here in Japan a gallon will cost $70 . I finally broke down and bought some and ordered some compressor airline. My plan is to make an old coil denitrator to create a low oxygen environment which is tough to do in my aquarium as I use an ozone generator. Run the deoxygenated water through the sulfur beads to remove the nitrate via the autotrophic bacteria, and then run the effluent through some crushed oyster shells which I hope to pick up at an oyster farm down the road. The ID of the coil is 5/16. Any ideas on how much of the airline I should use?

Cheers,

James

[Bonneville08]

Hi James,
I've referenced "The Reef Aquarium" Volume 3 (Delbeek/Spung) for this answer.
The reactor design discussed in the book, does not mention coils of tubing like there were in older denitrators. The oxygen is consumed in the first part of the sulfur bed.
The book has some guidlines for size, amount of sulfur used and flow rates as well as direction of flow in a vertical design.
If you wish to follow the design mentioned in TRA, please PM me and I will provide details, otherwise I would say the length of tubing depends on your flow rate through the reactor. I used about 10 feet of poly tubing in my old FW denitrator with about 30 drops per second effluent.
Good luck

[Okayamapiper]

Bonneville08,
Thank you for the information. I've read about the designs on the net as well, but what confused me about the dual sulfur chambers is that the sulfur houses anaerobic bacteria to do the reduction of nitrate to nitrogen.
As I've finished the coil, I will put a pipe filled with sulfur which would then overflow into a 1/2 pipe to let the effluent go into an oyster shell chamber which would then drip into my sump.

Hopefully this will work as I would like to get nitrates to zero as I just got back from the ocean where I picked up some awesome sps pieces.

Cheers,

James

[reef4gsp]

I've spent Oh Too many hours online reasearching this topic. Here are some from my favorites list:

Chemistry and the Aquarium

kalkwasser
I hope you understand basic chemistry!

The reason I add the link to the Kalkwasser page is because the biggest problem to this system will be the low pH and Alk of the effluent. This is why some systems employ a second chamber.My Idea is to have a chamber where both the effluent of the sulfur reactor and Kalk can be dripped. Bringing the pH of the combined effluent to an acceptable level.

I've read nothing but good about these and will be starting my own soon. I would first like to know if the pH inside the reactor affects bacterial growth.

Your coil is a good idea. You can find designs for those type of denitrators online and I would use those specs as a guide line for the length you need. This would probably increase the efficency of the sulfur reactor.

Here's a summary of recommendations by fellow aquarists:
Use a recirculating pump.
A dual chamber is better than a single.
A 1 part sulfur media, 3 parts calcium medium is suggested.
The sulfur media chamber should be opaque to prevent algae growth(photosynthesis+CO2 =O2)(O2= no anaerobic bacteria).
The effluent should be dripped into an area where aeration will occur, such as a skimmer box.

I feel the effluent could be combined with Kalk as described above, or dripped into a refugium, where excess CO2 could be absorbed by macroalgae and phytoplankton, assuming they could survive in such a nutrient-free system, seagrasses are more likely phospate-limited in growth and would be more suitable.

Great Luck to you on your build and post progress/results!!!

[Okayamapiper]

I finished winding the coil inside a 40 inch long 4 inch diameter acrylic pipe. The pipe bottom has a 1/2 PVC pipe which runs up the middle. The space between the coil and the PVC pipe is filled with CaribSea LSM, so the water will run down the coil to the bottom, up through the LSM until it overflows back down the PVC to an Eheim prefilter cannister filled with CaribSea ARM (aragonite reactor media) which then goes through a valve and into my sump. The aragonite will do the same as a Kalk reactor with the added benefits of adding other trace elements. I hope to finish setting it up in the next couple of days.

I shall provide photos of the construction then.

Cheers,

James

[reef4gsp]

Canister? How fast do you intend your flow to be? Can't wait to see more! Post it up!

[Okayamapiper]

In the interest of time and knowing I love to put things off, I opted for the simple gravity fed coil to LSM and then siphoned to my Eheim prefilter canister filled with ARM. The output of the canister is cut down to a CO2 airline with valve which is then dripped into the sump. Flow is acceptable. I can get a full stream, but at the moment it is dripping in at 1 drip every 1.5 seconds.

[Okayamapiper]

Jus an update.
Tank nitrate levels are dropping slowly. They were around 40ppm and are now down to 30. Effluent is running about 10ppm and am debating whether to slow down the drip or wait for the bacteria to multiply and take up the slack. I am sure the SPS are happier now and should be even more happy in about 10 days as at the current rate of nitrate depletion I should be reaching zero around then

PH is holding around 8.2. I used 1 gallon of LSM and 1 gallon of ARM. The LSM tube is 1 meter tall by 9.5cm wide with an 8mm coil wrapped inside (around 50 ft). The water comes from the top of the aquarium to the top of the tube, runs down to the bottom and then goes back up the center which is filled with LSM. It then overflows into an Eheim for a very slow drip. The water in the LSM is siphoned into the acrylic tube and sits there a while before the Eheim drips it into the sump which is filled with some more ARM and a bunch of live rock.

Cheers,

James

[reef4gsp]

Thats Awesome!!! What's the Ph and nitrite of the effluent? Once it stops producing nitrite is when you should turn it up.

Looking forward to more updates

[Okayamapiper]

Ph of effluent is running around 7.9 and nitrate is zero. The main tank nitrate is down to 5mg/l . Currently I am letting it drip at 1 drip/second which comes to about 20 liters a day. As my tank is 120 liters, I don't see any need for a pump and will let it run on gravity.

[reef4gsp]

What I'm worried about is that if the pH of the effluent is -0.3 off target at 20LPD then you would need an additional source of pH of +0.3 of your target at an equal flow to maintain long term stability. Has it affected your DkH at all?

Your effluent pH seems to be higher than other reefers across forums I've read.

What are you using to control flow?

[Okayamapiper]

The effluent from the denitrator drips into a chamber where I drip kalkwasser. The tank has a DSB full of aragonite, so it should be amply buffered if the Kalk proves insufficient. So far, I've noticed increased growth of acro. coral.

The reason for the Ph being being off target is that I used 3.6 liters of sulfur which is 3% of my tank volume instead of the recommended 1%. The recommended amount of reactor media is 3 times that of the sulfur, but due to a lack of tubing and canisters, I only have 1/3 of the media recommended. For this reason I drip Kalk to compensate. Tank Ph is stable so far, but I will need to keep an eye on it to confirm the Kalk and DSB are doing their job. Once I can get my hand on some more acrylic pipe, I will build a huge ARM reactor to neutralize all of the effluent.



James

[jimw369]

Originally Posted by Okayamapiper

In the interest of time and knowing I love to put things off, I opted for the simple gravity fed coil to LSM and then siphoned to my Eheim prefilter canister filled with ARM. The output of the canister is cut down to a CO2 airline with valve which is then dripped into the sump. Flow is acceptable. I can get a full stream, but at the moment it is dripping in at 1 drip every 1.5 seconds.

You might get algae growing inside your tubing.

[reef4gsp]

Originally Posted by Okayamapiper

The effluent from the denitrator drips into a chamber where I drip kalkwasser. The tank has a DSB full of aragonite, so it should be amply buffered if the Kalk proves insufficient. So far, I've noticed increased growth of acro. coral.

The reason for the Ph being being off target is that I used 3.6 liters of sulfur which is 3% of my tank volume instead of the recommended 1%. The recommended amount of reactor media is 3 times that of the sulfur, but due to a lack of tubing and canisters, I only have 1/3 of the media recommended. For this reason I drip Kalk to compensate. Tank Ph is stable so far, but I will need to keep an eye on it to confirm the Kalk and DSB are doing their job. Once I can get my hand on some more acrylic pipe, I will build a huge ARM reactor to neutralize all of the effluent.
James

If you read the Kalkwasser link I provided above, the increase in SPS growth [assuming increased calcium levels are the cause] could be attributed to the increased level of CO2 in the effluent, as the Kalk is dripped it uses Co2 in the water to dissolve, not enough CO2 causes precipitation of calcium bicarbonate, abundant CO2 allows solution, thus, the effluent of the reactor is increasing the efficiency of the kalk drip.

Aragonite (calcium bicarbonate) typically desolves at a Ph lower than desirable for a reef or even FOWLR and and while I beleive it will save a tank from an acidic death, I don't beleive it alone would maintain a high PH with such an acidic piece of equipment in use. Your use of kalk (with this system) is IMHO the best way of maintaining long term PH.

Jim has a point. I wanted to use acrylic but decided against it because it lets algae grow and produce oxygen instead I will use two 24" long 6" diameter PVC pipes from Home Depot. I would suggest either painting your sulfur chamber OR buying something else as a sulfur chamber and using that nice pretty acrylic tube for the aragonite media chamber.

I love your system though and applaud you for jumping into this international amature experiment.

[Okayamapiper]

I too in my earlier attempts at a coil denitrator years ago made the mistake of using translucent piping for the coil and reaction chambers which ended up with clogged pipes and tons of algae. To correct this issue, I used orange airline hose, so there is no light for algae to grow. I coiled this along the entire length of the acryclic tube, so no light gets into it, so in essence I wasted a pretty tube when PVC would have been the cheaper alternative, but the tube was left over material from some overflow tanks I built for friends, so it was free.

The reason for the coil/sulfur denitrator design is that I use an ozonizer with my Berline Classic skimmer, so I have oxygen level near fully saturation which the type of water I want to expose anaerobic bacteria to.

I also use aluminum oxide in the sump to remove any phosphates so I have never had much of a problem with algae, though dripping Kalk and elevating the calcium levels in the tank will precipitate any phosphate in the tank as calcium phosphate is insoluble in water, so the aluminum oxide may have become redundant. Do you think I should remove the aluminum oxide?

James

[Okayamapiper]

Just an update. Tank pH is 8.3, effluent is 7.9 running just short of a steady stream through airline tubing. Nitrates are 0. Calcium is 420. The flow is a tad slow and could use a pump as there is a hint of hydrogen sulfate, but as I have the sump heavily aerated with ozone added tot he mix, the hydrogen sulfide is oxidzed before getting into the main tank ( at least the corals and polyps have shown no problems).

My second coil denitrator has way too much backpressure and stops up when an air bubble builds up in the coil, so I will tear it down after Christmas and redesign it.
Cheers,

James

[reef4gsp]

I'd like to raise this from the dead, how's it going? Is it still up and running? Pics? I never attempted it. I got sidetracked and started building stands and hoods instead.

[Okayamapiper]

My first denitrator has photos in one of the earlier replies. The second denitrator is up and running as well. The flow problem was not a backpressure issue but a clogged T valve which I replaced with a plain elbow. Nitrates are zero in both tanks. pH on the second denitrator is 8.2 as I used considerably more ARM. I also included a bag of RowaPhos that the effluent from the reactor has to go through after the Aragonite Reactor Media, so I have zero nitrates, silicates and phosphates. It is a gravity fed system with a coil on the outside of a 1 meter 6 inch PVC pipe. It feeds into the bottom which is filled with bioballs. On top of the bioballs is a 6 inch round sponge. On top of the sponge is LSM and above it is ARM and finally RowaPhos. The pipe has a 1/4 pipe running up the middle so the water goes through the coil to the bottom, up through the bioballs and media and then overflows back down into the sump.

[Okayamapiper]

Here is a photo of my second denitrator. As written earlier, I use 6mm airline hose wrapped around a 4 inch PVC pipe. The water comes from the overhead refugium and is gravity fed down the airline coil and is robbed of oxygen by bacteria that has grown in it.



It reaches the bottom, goes through some rubble, then some LSM (Carib Sea granulated sulfur), some ARM (Carib Sea Aragonite Reactor Media), RowaPhos, and finally 100 grams of GAC (Granular Activated Carbon) at which point it hits the overflow and goes back down a 1/2 inch pipe to the sump.





By doing the above, I have managed to keep nitrates and phosphates to zero and keep calcium at 450 and pH at 8.2 . The only drawback is the unsightly pipe next to the tank, but it is a work in progress . I will be releasing the undulated trigger, clownfish, puffers and the lot back to the sea on my next trip and probably go back to a coral/seahorse tank though I need to build up a sizable pod population first.

[pmason44m]

Inspiring! The best version I've seen, very well done... the gravity system is just great, no issues with power/fail/etc. I too made a coil system but gave up after a couple weeks due to pump/flow concerns. But, it certainly did reduce nitrate very solidly.

I think I'll give it another go based on your design. Please post another report in a month or so and let me know how you're progressing.

Thanks so very much for sharing.

[Okayamapiper]

If fed from the main tank a power failure would be disasterous as the tank would empty. As I use an overhead fuge as the water source with only 5 gallons it is safe.
Thank you for the kind comments.
Cheers,
James

[bluenosedshellback]

Great to see another reefer in Japan, esp so close (I am in Iwakuni (Yamaguchi Pref.)). Anyhow, I also had a DIY Denitrator that I built for my tank prior to coming over to Japan. This was about two years ago so my memory is a little iffy. I was fortunate to have access to several hardware supply stores to ease the build. Mine in essence was 4 inch PVC tubing about 20 inches tall with flanges on each end. The foot was a special fitting that was designed for pipes going through floors. I used 1/4 inch clear tubing sound around the inside of the tubing.... the interior was filled with bioballs. I cannot remember how long the tubing was that I coiled inside.... just that it was a ridiculous length. For bullkhead fittings I used John Guest fittings and valves to control flow. The inlet was plumbed in off the main return pump. My reactor was designed to be a self sustaing design that did not have media which would eventually be exhausted and replaced.... the reason behind this was because of the long time it takes to cycle the unit... once the bacteria was established it would not need to be reopened again pending no failures. The unit worked flawlessly and had a small enough footprint to fit under the tank... best of luck, i will keep track of this post to see how it pans out

[Okayamapiper]

As I had extra PVC, I made another denitrator using 4inch PVC for the primary chamber. It has a coil on the inside, 1.2 liters of sulfur and aragonite ontop. The center has a 13mm id pipe to overflow to the bottom where it goes through the bottom of another 40mm pipe with aragonite. Pipe has an internal overflow which drips into my tank. Effluent reads zero for nitrate or nitrites. pH of effluent it 8.0 which is .2 off target and is gobbling up my dKH like it is going out of style...
I am using a Kent doser with Kalk to keep the dKH and pH from crashing, but I definitely need to build a 3rd chamber with some more aragonite or possibly a neilsen reactor using the effluent to feed it.