Poor Man's Nutrients Control - Donovan's Nitrate Destroyer

JGT

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That's correct. I have knock-out caps in there... but I did end up sealing them with silicone because they were sieves. So now they should be very secure with ZERO air/water getting in or out.
OK, and the caps on top of the towers?
 

JGT

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Those are just pushed on but pretty tightly. Not easy to get them off.

Everything else on the reactor is glued in place.
Thanks. Figured as much since it sounds like periodically may need to flush them out. Just got back from Home Depot. I made mine screw off cleanout caps so I can open if need be.
 

UncommonSense

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I actually happen to have an ancient XL Aquaripure denitrifier laying around which recently split a welded seam…

I plan to cut it apart both for proper disposal, and out of sheer mechanical curiosity…

Would anyone be interested in a documentation of the process, primarily to get firsthand photos of what’s inside these sealed black boxes which essentially work as a DND?

image.jpg
 

twentyleagues

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I actually happen to have an ancient XL Aquaripure denitrifier laying around which recently split a welded seam…

I plan to cut it apart both for proper disposal, and out of sheer mechanical curiosity…

Would anyone be interested in a documentation of the process, primarily to get firsthand photos of what’s inside these sealed black boxes which essentially work as a DND?

image.jpg
YES!
I had one of their smaller(still quite large) units back in the day. It went with the rest of the reef stuff when I sold my system. I always wondered what the proprietary secret was.
 

UncommonSense

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YES!
I had one of their smaller(still quite large) units back in the day. It went with the rest of the reef stuff when I sold my system. I always wondered what the proprietary secret was.
Well, I’ll do a destructive autopsy then, for science!

(When I find time to do the job) I’ll probably make a new thread in DIY detailing it, then post a link and internals pic(s) here!
 

twentyleagues

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Well, I’ll do a destructive autopsy then, for science!

(When I find time to do the job) I’ll probably make a new thread in DIY detailing it, then post a link and internals pic(s) here!
I have a feeling its coils of tubing or some kind of multi-sized mesh. I saw a youtube video with someone who made a knock off unit and they said it was from "insider info" on the build. I believe these had some kind of patent on them when they came out.
 

Saltees

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Finally got my DND running on the 90G (350L) tank with 3 dragon morays. Tank’s pretty simple — no filter, just a coral chip bed with PVC pipes and fittings. Still, nitrates were stuck at 300+ ppm for over a month, even with 80% weekly water changes.

The DND is a DIY 36" tall × 4" dia twin-chamber with a ¾" interlink. Aerobic side’s stuffed with Siporax, anaerobic side has Maxspect Biosphere at the bottom, topped with Seachem De-Nitrate mixed with K1 to stop it from clogging up.

Seeded it for 3 days with 100ml Brightwell Microbacter 7, then started daily dosing 20ml DIY NOPOX.

By week 3, nitrates finally dropped to ~20 ppm. Pretty stoked it worked so quickly.

camphoto_1483920592.jpeg
 
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McPuff

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Finally got my DND running on the 90G (350L) tank with 3 dragon morays. Tank’s pretty simple — no filter, just a coral chip bed with PVC pipes and fittings. Still, nitrates were stuck at 300+ ppm for over a month, even with 80% weekly water changes.

The DND is a DIY 36" tall × 4" dia twin-chamber with a ¾" interlink. Aerobic side’s stuffed with Siporax, anaerobic side has Maxspect Biosphere at the bottom, topped with Seachem De-Nitrate mixed with K1 to stop it from clogging up.

Seeded it for 3 days with 100ml Brightwell Microbacter 7, then started daily dosing 20ml DIY NOPOX.

By week 3, nitrates finally dropped to ~20 ppm. Pretty stoked it worked so quickly.

camphoto_1483920592.jpeg
Wow that is a huge drop in NO3. My reactor has been set up for almost two months and I've seen a pretty substantial decrease (~50%) but last test was still around 100ppm and the effluent was somewhere around 50. I need to get a hannah checker to get more precise readings though... hard to tell what shade of pink is actually showing up. :0)

Would be cool to see a pic or two of the dragons!
 

Saltees

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Yeah, I’m on the Hanna too—equally surprised at how fast it’s been knocking NO3 down.

And haha, sure thing—I’ll grab a few dragon shots next feeding and post them here 🐉🐉🐉
 

Curiousbranching

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Finally got my DND running on the 90G (350L) tank with 3 dragon morays. Tank’s pretty simple — no filter, just a coral chip bed with PVC pipes and fittings. Still, nitrates were stuck at 300+ ppm for over a month, even with 80% weekly water changes.

The DND is a DIY 36" tall × 4" dia twin-chamber with a ¾" interlink. Aerobic side’s stuffed with Siporax, anaerobic side has Maxspect Biosphere at the bottom, topped with Seachem De-Nitrate mixed with K1 to stop it from clogging up.

Seeded it for 3 days with 100ml Brightwell Microbacter 7, then started daily dosing 20ml DIY NOPOX.

By week 3, nitrates finally dropped to ~20 ppm. Pretty stoked it worked so quickly.

camphoto_1483920592.jpeg
I think the decrease in NO3 is mainly due to the growth of heterotrophic bacteria and aerobic bacteria. Anaerobic bacteria only truly become active when the DND outlet no longer accumulates a layer of bacterial biofilm.
 

Saltees

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Finally got my DND running on the 90G (350L) tank with 3 dragon morays. Tank’s pretty simple — no filter, just a coral chip bed with PVC pipes and fittings. Still, nitrates were stuck at 300+ ppm for over a month, even with 80% weekly water changes.

The DND is a DIY 36" tall × 4" dia twin-chamber with a ¾" interlink. Aerobic side’s stuffed with Siporax, anaerobic side has Maxspect Biosphere at the bottom, topped with Seachem De-Nitrate mixed with K1 to stop it from clogging up.

Seeded it for 3 days with 100ml Brightwell Microbacter 7, then started daily dosing 20ml DIY NOPOX.

By week 3, nitrates finally dropped to ~20 ppm. Pretty stoked it worked so quickly.

camphoto_1483920592.jpeg
I think the decrease in NO3 is mainly due to the growth of heterotrophic bacteria and aerobic bacteria. Anaerobic bacteria only truly become active when the DND outlet no longer accumulates a layer of bacterial biofilm.
Right, you’re so right. I ran a UV a week ago, cos the water was smelling bad and thick foam was accumulating on the surface, and the DND was my only filtration. This week, smell and foam’s gone, water’s clear too. And I just tested the water, the NO3 was backed to 300ppm!
 

UncommonSense

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I have a feeling its coils of tubing or some kind of multi-sized mesh. I saw a youtube video with someone who made a knock off unit and they said it was from "insider info" on the build. I believe these had some kind of patent on them when they came out.
Well, I got the ol’ Aquaripure black box cut apart… it was a bit hilarious!


IMG_8548.jpeg
 

twentyleagues

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Well, I got the ol’ Aquaripure black box cut apart… it was a bit hilarious!


IMG_8548.jpeg
Well I was expecting a coil of something! I paid way too much for that unit.
 

UncommonSense

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Well I was expecting a coil of something! I paid way too much for that unit.
Built back when acrylic was cheap, apparently…

I’m sorry for the sad news on that front, but now we know! — all that is technically required is a lidded bucket full of filter floss, plus a few small bulkhead fittings!
 

twentyleagues

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Built back when acrylic was cheap, apparently…

I’m sorry for the sad news on that front, but now we know! — all that is technically required is a lidded bucket full of filter floss, plus a few small bulkhead fittings!
Maybe I'll try it! I have a "canister" filter rolling around in the garage somewhere I built off the guy on the utube that didnt work like he said it did. Well, it did work as long as power stayed on. No way a gamma lid can hold that pressure in power off under any decent sized tank. I didnt even test it on a tank. I tested it with a 20g tote and it failed every time power was off for more than a minute. I used it over a tank for maybe a year and it worked fine if you like canister filters over your tank. I can probably mod it in its current config to do this.
 

UncommonSense

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Maybe I'll try it! I have a "canister" filter rolling around in the garage somewhere I built off the guy on the utube that didnt work like he said it did. Well, it did work as long as power stayed on. No way a gamma lid can hold that pressure in power off under any decent sized tank. I didnt even test it on a tank. I tested it with a 20g tote and it failed every time power was off for more than a minute. I used it over a tank for maybe a year and it worked fine if you like canister filters over your tank. I can probably mod it in its current config to do this.
Hmm… really? 6ft of well height is <3psi… surely a bucket sees more than that just sitting out on a hot day!
 

twentyleagues

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Hmm… really? 6ft of well height is <3psi… surely a bucket sees more than that just sitting out on a hot day!
The seal on the gamma lid would start dripping then spraying. I used 2 buckets and 4 lids trying to replicate his build, all failed. So did his diy overflow pvc pipe set up. Well again, the overflow worked but with only about a 1/4 of the flow he showed, and it would easily lose prime. Tried that one a few times and quit also.
 

Curiousbranching

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Right, you’re so right. I ran a UV a week ago, cos the water was smelling bad and thick foam was accumulating on the surface, and the DND was my only filtration. This week, smell and foam’s gone, water’s clear too. And I just tested the water, the NO3 was backed to 300ppm!
Yes, I noticed this during the process of putting the DND into operation a few months ago. In the first month, I frequently experienced clogging in the DND outlet due to bacterial buildup. Although NO3 and PO4 in the tank decreased, I knew it was due to heterotrophic bacteria. Therefore, I reduced the flow rate to about 1–2 drops per second and divided the carbon dose into smaller amounts, setting it to automate 8 times per day, 0.3ml each time. After about half a month, I no longer observed bacterial accumulation in the outlet, and my NO3 dropped from around 40–50 ppm to 0–5 ppm.
 

Saltees

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Wow that is a huge drop in NO3. My reactor has been set up for almost two months and I've seen a pretty substantial decrease (~50%) but last test was still around 100ppm and the effluent was somewhere around 50. I need to get a hannah checker to get more precise readings though... hard to tell what shade of pink is actually showing up. :0)

Would be cool to see a pic or two of the dragons!
As promised my “Hydras”, unfortunately through the literally bolted down netting… can’t afford them escaping… will post better pics down the road. They actually like each other’s company at times.
 

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