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How do you lower Nitrates

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Sandbeds are a great way of reducing nitrates but it also develops a layer of sulfur after a while. Just look up old tank syndrome. I'm using a Koralin denitrator to bring my nitrates from over 100 to under 20. Not sure i'll get below 1 ever with a denitrator alone.
 
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Sandbeds are a great way of reducing nitrates but it also develops a layer of sulfur after a while. Just look up old tank syndrome. I'm using a Koralin denitrator to bring my nitrates from over 100 to under 20. Not sure i'll get below 1 ever with a denitrator alone.

Just to clarify this, DEEP sand beds (>3") allow for anaerobic bacteria to grow which can process nitrates. This type of bacteria growth only occurs in places where there is a lack of oxygen. One of the byproducts of the anaerobic bacteria processing nitrate is hydrogen sulfide. The sulfide/sulphur comes if you disturb the anaerobic bacteria by moving or stirring the sand.

You will not have anaerobic bacteria in sand beds that are 2" or less.

It is possible though to have this occur in sand under rocks that have little to no flow regardless how deep the sand is. You'll know if it's anaerobic bacteria is there if the sand or rocks turn black as that's a sign of an anoxic area and hydrogen sulfide being produced.
 
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Sandbeds are a great way of reducing nitrates but it also develops a layer of sulfur after a while. Just look up old tank syndrome. I'm using a Koralin denitrator to bring my nitrates from over 100 to under 20. Not sure i'll get below 1 ever with a denitrator alone.
Where do you source your sulfur media?
 
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Just to clarify this, DEEP sand beds (>3") allow for anaerobic bacteria to grow which can process nitrates. This type of bacteria growth only occurs in places where there is a lack of oxygen. One of the byproducts of the anaerobic bacteria processing nitrate is hydrogen sulfide. The sulphate/sulphur comes if you disturb the anaerobic bacteria by moving or stirring the sand.

You will not have anaerobic bacteria in a sand beds that are 2" or less.
Denitrator systems like the one mentioned above rely on anaerobic bacteria to get nitrates to zero on the effluence end which don’t need to be in the dark since getting a jump from sulfur media.. Been thinking of turning an old calcium reactor into one.. Wonder why their not more popular as long as you get a big enough one to turn over your water faster GPH keeping up with your system..
IMG_7652.jpeg
 
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thats the smaller unit. you’ll want a bigger one for higher bioload. the only problem with these is they get clogged. so dont gravity feed it. make sure its plumbed to the return pump and then just regulate the output at 1-2 drops a second.

you do need to keep an eye on it every once in a while. if its working over time initially it will fill up with nitrogen gas and you need to purge it (easy to do)
 
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Just to clarify this, DEEP sand beds (>3") allow for anaerobic bacteria to grow which can process nitrates. This type of bacteria growth only occurs in places where there is a lack of oxygen. One of the byproducts of the anaerobic bacteria processing nitrate is hydrogen sulfide. The sulfide/sulphur comes if you disturb the anaerobic bacteria by moving or stirring the sand.

You will not have anaerobic bacteria in a sand beds that are 2" or less.

It is possible though to have this occur in sand under rocks that have little to no flow regardless how deep the sand is. You'll know if it's anaerobic bacteria is there if the sand or rocks turn black as that's a sign of an anoxic area and hydrogen sulfide being produced.
I’ve seen blue color in deep sand before and assumed that I was seeing annerobic bacteria. Maybe there’s multiple types. I’ve seen some black before too, but not usually in active systems
 
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I had, well still have, a rdsb on my system. I am a hedge bet reefer, so because I had the space and an RDSB is cheap and easy it still goes. It was going when my nitrate was way high. Pretty much nothing I did impacted my nitrate and phosphate. Untill about 6 months after I stared doing auto water changes.
How are your nitrates now? After 6 month of AWC? How much water is this within a week? And your AWC are with natural seawater, correct?
 
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