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

[Neil Cohen]

Loving mine. Nitrates and phos dropped too quickly and bottomed but was able to manage with more feedings(my goal anyway)

now nitrates have been steady at 10-12, phos is up and down, so I added an export plate. Rather get it as low as possible and dose, better for stability

only issue I have had is the output clogging, so I may make a bigger outlet.

 

[Steve2020]

Loving mine. Nitrates and phos dropped too quickly and bottomed but was able to manage with more feedings(my goal anyway)

now nitrates have been steady at 10-12, phos is up and down, so I added an export plate. Rather get it as low as possible and dose, better for stability

only issue I have had is the output clogging, so I may make a bigger outlet.

Clogging was an issue I was curious about. I am assuming you don't want to clean these out on a regular basis because you would lose the bacteria colony. May I ask what diameter pipe size and length along with the media you are using and you total water volume of your tank/sump?

 

[Neil Cohen]

Sorry, not clogging inside, that is the reason behind the variety of mediums. It’s clogging at the tubing connector, which is airline tubing. Going to change it to 1/4”. Just have to monitor it and pull off the tubing periodically.

 

[Steve2020]

Curious on how the DND has been working for everyone? I am in the process of slowly reducing my DIY carbon source to zero due to the AcroPower along with Carbon dosing has caused a small ( so far ) Dino outbreak. I ran across this yesterday and I am very interested on building one and giving it a try. I do have a lot of questions about the build but will hold of on those once I hear some feedback on how things a going with everyone's DND.
Thank you.

So, I didn't get much feedback on how this has been working long term for everyone so I have a couple questions. I have 250gal total water volume and plan on using 4" PVC because 6" components seem to be difficult to obtain. I want to put this in my stand which has 36" of head room so I would like to use two 4"x24" tubes and when including all the adapters would be approx 32-33" per side. Will this work for250gal? Flow will be approx 1gal/hr.

 

[Neil Cohen]

I’ve had mine running about six months and it’s been pretty solid.

still having some issues keeping the phos low but nitrates have been steady.

if/when I rebuild it, I would definitely use 4” or 6” if I can find it. Much more expensive to build but tons more surface area and less chances of blockages. I will also have bigger in and out feeds. Too easy for the fittings to get clogged with “snot”.

i also would put a back flow and waste tube. The first time it clogged, the pressure built and it found a way to leak (better than exploding)

cleared it my hooking a small pump to the output and blowing it out the other side. It was a mess bc it wasn’t set up for it

 

[Steve2020]

I’ve had mine running about six months and it’s been pretty solid.

still having some issues keeping the phos low but nitrates have been steady.

if/when I rebuild it, I would definitely use 4” or 6” if I can find it. Much more expensive to build but tons more surface area and less chances of blockages. I will also have bigger in and out feeds. Too easy for the fittings to get clogged with “snot”.

i also would put a back flow and waste tube. The first time it clogged, the pressure built and it found a way to leak (better than exploding)

cleared it my hooking a small pump to the output and blowing it out the other side. It was a mess bc it wasn’t set up for it

Do you believe the size and length I mentioned work for denitrification for 250gal?

 

[Neil Cohen]

I’m the wrong person to ask. Mine is running on a 100g mixed reef with a sump. My build was about available space calculations and cost of fittings more than bio load.

as I understand it, the dnd can’t have a fast turnover or it will pass though without breaking down the nitrate. If space want a limitation, I hold build it as big as I could, then dial it up and down till my nitrates were steady where is wanted, the. Up the feeding, tune, repeat.

main w I had budget and space issues, I took what this bulls gave me, added a turf scrubber and an export plate. Even kept carbon dosing. I knew I was risking Dino’s and other low nutrient problems but testing almost daily, I was able to adjust the return rate so the turn over helped level it out. Still have some stability issues with phos

 

[Steve2020]

Today I purchased most of the components for my build. It will be approx 4"x5'. One of the recommended bio media is large ceramic rings. What is considered large? The largest I can find is 1/2"x1/2". Is that considered large?
Any media recommendations would be appreciated.

 

[Steve2020]

Today I purchased most of the components for my build. It will be approx 4"x5'. One of the recommended bio media is large ceramic rings. What is considered large? The largest I can find is 1/2"x1/2". Is that considered large?
Any media recommendations would be appreciated.

Does the thumbs up mean 1/2"x1/2" is fine for ceramic rings?

 

[wmb0003]

I used a combination of these 3 in mine
hygger 6.2-Inch Long Large Aquarium Filter Media, Ceramic Bio Media Blocks for Sump Tank Pond Fish Tank Media 7.9 LBs 40-Pack https://a.co/d/g1EfMgP
AQUANEAT Bio Ceramic Rings 6 lbs Aquarium Sump Filter Media Fish Tank Koi Pond Canister Filter Media in 6 Free Mesh Bags https://a.co/d/3oyl6un
Reefing Art Filter Media Bio Filter Rings Ceramic Media 140ct / 2 lbs / 4 lbs / 8 lbs https://a.co/d/ft8LKc5

 

[JMM744]

Do not use small stuff. It clogs. I bought some and mixed with large and in the end removed all the small media and replaced with large ceramic balls. After a couple weeks it will slow down due to the snot formed by bacteria but I gently increase flow till it flushes some. Too fast and it clouds the sump. You could also rig a filter or run it into a bucket to flush it faster.
Amazon product ASIN B00HT2ARFU

 

[Steve2020]

Do not use small stuff. It clogs. I bought some and mixed with large and in the end removed all the small media and replaced with large ceramic balls. After a couple weeks it will slow down due to the snot formed by bacteria but I gently increase flow till it flushes some. Too fast and it clouds the sump. You could also rig a filter or run it into a bucket to flush it faster.
Amazon product ASIN B00HT2ARFU

Thanks. I have some already on order. Flushing will not be an issue. I have a 1 and 10 micron sock I had for filtering tank water when cleaned my sand when I had Dino's.

 

[Steve2020]

I used a combination of these 3 in mine
hygger 6.2-Inch Long Large Aquarium Filter Media, Ceramic Bio Media Blocks for Sump Tank Pond Fish Tank Media 7.9 LBs 40-Pack https://a.co/d/g1EfMgP
AQUANEAT Bio Ceramic Rings 6 lbs Aquarium Sump Filter Media Fish Tank Koi Pond Canister Filter Media in 6 Free Mesh Bags https://a.co/d/3oyl6un
Reefing Art Filter Media Bio Filter Rings Ceramic Media 140ct / 2 lbs / 4 lbs / 8 lbs https://a.co/d/ft8LKc5

One last question, with your setup are you having clogging issues with the Bio Ceramic Rings? I think I should be fine with the size of my setup because I can run a higher flow from everything I have read. I would only put the Bio Rings on the bottom of the two 5ft tubes.

 

[wmb0003]

One last question, with your setup are you having clogging issues with the Bio Ceramic Rings? I think I should be fine with the size of my setup because I can run a higher flow from everything I have read. I would only put the Bio Rings on the bottom of the two 5ft tubes.

I have shorter tubes, probably 2-3 ft. I used 4” pvc also.

The only clogging that I get is on the output line, I am using 1/4” John’s guest tubing(same as RODI). I should make it bigger but when it gets clogged up, I just shake the gunk loose off the end and then blow in it, haha.

 

[Steve2020]

Just finished putting the DND together and leaked test. NO LEAKS:). One thing I still need to do to it besides figure out all the media to use is to add the emergency overflow. I have 2 options and not sure which would be better. Either put a Tee where the dosing push connect is or to drill a hole in the PVC. My first option is to do the Tee Fitting for easy plug and play but I am not sure how watertight the cleanout plugs are. I have the plugs wrapped in Teflon Tape to prevent galling. I also have some T Plus2 Thread Sealant that may prevent any leakage. The DND is not pressurized so I am think the plugs should not leak.
Any thoughts on the emergency drain?

 

[Steve2020]

I posted this on another thread. 30 views but no response so I will post it here and hopefully someone knows the answer.
"I built a denitrification system ( NON PRESSURIZED ) and adding an emergency overflow in case of clogging. In the photo below is one of my ideas but not sure if I will create an issue with the auto dosing of DIY NoPox. The vertical tube is the dosing tube and the right angle tube is the emergency overflow. Internally to the John Guest Tee Fitting when the doser stops pumping will the NoPox fluid level within the fitting be slightly above the right angle portion of the fitting due to atmosphere? What I don't want to happen is to backflow the dosing tube. Normal water level will be approximately where my finger is. I also attached a photo of the unit during my leak test today."




My other option is to drill a hole in the ROUND PVC PIPE and silicone in either a push connect fitting or a tube which I prefer not to do.

 

[wmb0003]

I am not sure, I have mine built so it is in sump so if it overflows no big deal. The main reason mine clogs is because the small output clogs. Mine will overflow out of the top where my dosing and feeding holes are(they are just holes drilled a little bigger than my airline tubing.) If I were in your shoes, I would drill a larger hole a few inches above where your finger is and have a larger hose as an overflow. My concern with your current setup is some of that slime could clog up in the T where your dosing/overflow is. If everything is sealed properly though, the pump should either push the slime out the emergency or output or just not have the strength to pump water in due to the pressure.

 

[Steve2020]

I am not sure, I have mine built so it is in sump so if it overflows no big deal. The main reason mine clogs is because the small output clogs. Mine will overflow out of the top where my dosing and feeding holes are(they are just holes drilled a little bigger than my airline tubing.) If I were in your shoes, I would drill a larger hole a few inches above where your finger is and have a larger hose as an overflow. My concern with your current setup is some of that slime could clog up in the T where your dosing/overflow is. If everything is sealed properly though, the pump should either push the slime out the emergency or output or just not have the strength to pump water in due to the pressure.

Thanks for the recommendation. The unit is sealed and air tight. I believe I will be able to run this at a higher flow rate due to the 10ft total pipe length. Even if I follow the 10% rule that would be 25gal/day. I think I will add a check valve on the dosing line once I determine that the dosing pump can create enough break/crack pressure which I believe they can. If all else fails I can do the drill the hole thing later and seal the hose in place with silicone.
The pump that will feed this unit is a Vectra M2 that also feeds my UV so I will have plenty of pressure if needed to flush the system.

 

[slr]

nice

 

[Steve2020]

nice

Waiting for all the media to arrive before I hook it up to the tank. Some wont arrive until next week. 5 different medias.