Nitrate and the FOWLR

wheel6251

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Happy new year everyone. My son and I keep a 180 gallon fowlr tank. We have a variety of angelfish, tangs and some miscellaneous fish. The tank has been up about a year. We currently use two FX6 filters to keep it clean. I am struggling to keep my nitrate down. Here are two suggestions I’ve gotten recently. The first one was, who cares about nitrate? It doesn’t bother the fish. Two, take the filter foams out of the fx6’s and replace it with maxspect biospheres. We have about 180 pounds of live rock, and 2 to 3 inches of black sand in the tank as of this writing. Thanks in advance for any opinions you may have.
 
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wheel6251

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I would say its about 60 ppm on a API test kit. I have hanna test for ammonia and copper, but not nitrate. I also just tested my RODI water and its 0 ppm.
 
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wheel6251

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I would say its about 60 ppm on a API test kit. I have hanna test for ammonia and copper, but not nitrate. I also just tested my RODI water and its 0 ppm.
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Mr. Mojo Rising

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Canisters do well to keep the water clean but they don't "export" the nutrients. A Protein skimmer or a refugium or water changes are examples of ways to "export" nutrients from your system. Carbon dosing is another method buts that more advanced than I am.
 

GT3000XX

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I agree you definitely need to add a properly sized protein skimmer. Canisters can be nitrate factories.
 

Largeangels

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Sump with filter socks (if you replace or clean often), Protein skimmer and carbon dosing. You want to export the waste before it is broken down.
 

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I can test my tank when I get a chance and let you know, but for the longest time when I had two 150-gallon tanks loaded with heavy/messy eaters (Trigger fish, large Angels and large Wrasses, etc.) I routinely ran my tanks at 160+ Phosphates with no apparent harm to the fish. (Nitrates at 10.)
 

fish_collector

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I couldn't say what the nitrate level is in my FOWLR, I never test it and the fish are healthy and happy. I do however have a sump, filter sock and skimmer running. I'll test nitrate in a bit and report back, this thread has me curious now lol.
 

kboogie

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I have a 300G FOWLR that I keep well-stocked and feed six times a day. I do a big frozen food feeding each morning, followed by five half-teaspoon feedings of pellets to keep my anthias happy. I normally keep my nitrates at 0 by using a sulfur denitrator. My feed pump for the denitrator died after three years, so hetetrophic bacteria died. I'm currently re-establishing the denitrator, but when established after a few weeks it my nitrates will be back to 0, there are currently 18, which I do not like.

It is a fact that MOST, not all, fish are significantly less sensitive to nitrates. In my experience, I have noticed no impact until around 60ppm, and even then, those impacts are minimal. In my experience, around 160 ppm, you start to see impacts, when you get about 320ppm those impacts become obvious for the lesser tolerant fish. Around 600ppm only your hardiest fish (groupers, damsels, triggers, etc) show minimal impact and the lesser tolerant fish butterflies, tangs, and many angels start to die.

I think it is rare to get nitrates high enough to the level you are killing most fish. That doesn't mean you should not keep them at a level where you know you are having no impact on the fish.

For me, the biggest issue with nitrates is that they dramatically increase the rate of algae growth, which impacts the appearance of the display.

In addition to the sulfur denitrator, which has been a godsend, I use a large protein skimmer and an ozone generator.

In closing, while a FOWLR doesn't have anything close to the level of nitrate sensitivity of a reef with coral, it does not have unlimited tolerance for nitrates, and you should manage nitrates just not as closely as you would if you had corals.
 

JumboShrimp

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OOPS. I had typo'd my Nitrates and Phosphates in post #9. 😵‍💫 (I meant Nitrates 160+, Phosphates 10. Not vice-versa.)

In my current 150 gallon Butterfly tank (FOWLR), close to 0 Nitrates**, 10 Phosphates. I feed a lot (about 8 times a day)-- but not like I used to feed Triggers, large Angels, Wrasses, etc. What a difference!

(** That was API. Just got a 64.0 Nitrate test with Hanna Checker-- so let's go with that, obviously.)
 
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Simo2004

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I have a 300G FOWLR that I keep well-stocked and feed six times a day. I do a big frozen food feeding each morning, followed by five half-teaspoon feedings of pellets to keep my anthias happy. I normally keep my nitrates at 0 by using a sulfur denitrator. My feed pump for the denitrator died after three years, so hetetrophic bacteria died. I'm currently re-establishing the denitrator, but when established after a few weeks it my nitrates will be back to 0, there are currently 18, which I do not like.

It is a fact that MOST, not all, fish are significantly less sensitive to nitrates. In my experience, I have noticed no impact until around 60ppm, and even then, those impacts are minimal. In my experience, around 160 ppm, you start to see impacts, when you get about 320ppm those impacts become obvious for the lesser tolerant fish. Around 600ppm only your hardiest fish (groupers, damsels, triggers, etc) show minimal impact and the lesser tolerant fish butterflies, tangs, and many angels start to die.

I think it is rare to get nitrates high enough to the level you are killing most fish. That doesn't mean you should not keep them at a level where you know you are having no impact on the fish.

For me, the biggest issue with nitrates is that they dramatically increase the rate of algae growth, which impacts the appearance of the display.

In addition to the sulfur denitrator, which has been a godsend, I use a large protein skimmer and an ozone generator.

In closing, while a FOWLR doesn't have anything close to the level of nitrate sensitivity of a reef with coral, it does not have unlimited tolerance for nitrates, and you should manage nitrates just not as closely as you would if you had corals.
Hi have you any info on ur sulphate reactor

I'm trying to lower my no3 so having a read around
 

kboogie

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I have a 300G FOWLR that I keep well-stocked and feed six times a day. I do a big frozen food feeding each morning, followed by five half-teaspoon feedings of pellets to keep my anthias happy. I normally keep my nitrates at 0 by using a sulfur denitrator. My feed pump for the denitrator died after three years, so hetetrophic bacteria died. I'm currently re-establishing the denitrator, but when established after a few weeks it my nitrates will be back to 0, there are currently 18, which I do not like.

It is a fact that MOST, not all, fish are significantly less sensitive to nitrates. In my experience, I have noticed no impact until around 60ppm, and even then, those impacts are minimal. In my experience, around 160 ppm, you start to see impacts, when you get about 320ppm those impacts become obvious for the lesser tolerant fish. Around 600ppm only your hardiest fish (groupers, damsels, triggers, etc) show minimal impact and the lesser tolerant fish butterflies, tangs, and many angels start to die.

I think it is rare to get nitrates high enough to the level you are killing most fish. That doesn't mean you should not keep them at a level where you know you are having no impact on the fish.

For me, the biggest issue with nitrates is that they dramatically increase the rate of algae growth, which impacts the appearance of the display.

In addition to the sulfur denitrator, which has been a godsend, I use a large protein skimmer and an ozone generator.

In closing, while a FOWLR doesn't have anything close to the level of nitrate sensitivity of a reef with coral, it does not have unlimited tolerance for nitrates, and you should manage nitrates just not as closely as you would if you had corals.
Hi have you any info on ur sulphate reactor

I'm trying to lower my no3 so having a read around
I have an AquaMaxx TS-3. They don’t make them anymore. Deltec and Korallin still make them.

This thread helped me get setup.


This thread is a long thread on a DIY Denitrator and it contains a ton of background on the science of it.

 

JumboShrimp

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1768881057811.jpeg

You can do an R2R search for my failed experience; I still have an unused unit still in the box, which was supposed to be for my second tank.
 

kboogie

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Hi have you any info on ur sulphate reactor

I'm trying to lower my no3 so having a read around
Here is another good thread with good information and suggestions:
 

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I have a 300G FOWLR that I keep well-stocked and feed six times a day. I do a big frozen food feeding each morning, followed by five half-teaspoon feedings of pellets to keep my anthias happy. I normally keep my nitrates at 0 by using a sulfur denitrator. My feed pump for the denitrator died after three years, so hetetrophic bacteria died. I'm currently re-establishing the denitrator, but when established after a few weeks it my nitrates will be back to 0, there are currently 18, which I do not like.

It is a fact that MOST, not all, fish are significantly less sensitive to nitrates. In my experience, I have noticed no impact until around 60ppm, and even then, those impacts are minimal. In my experience, around 160 ppm, you start to see impacts, when you get about 320ppm those impacts become obvious for the lesser tolerant fish. Around 600ppm only your hardiest fish (groupers, damsels, triggers, etc) show minimal impact and the lesser tolerant fish butterflies, tangs, and many angels start to die.

I think it is rare to get nitrates high enough to the level you are killing most fish. That doesn't mean you should not keep them at a level where you know you are having no impact on the fish.

For me, the biggest issue with nitrates is that they dramatically increase the rate of algae growth, which impacts the appearance of the display.

In addition to the sulfur denitrator, which has been a godsend, I use a large protein skimmer and an ozone generator.

In closing, while a FOWLR doesn't have anything close to the level of nitrate sensitivity of a reef with coral, it does not have unlimited tolerance for nitrates, and you should manage nitrates just not as closely as you would if you had corals.
My research also shows how effective a Sulfur de-nitrator works, do you have any concern or way to manage the buildup of Phosphorus? I would think that a refugium w/Chaeto would perform a nice 1-2 punch to both. Thoughts?
 

kboogie

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My research also shows how effective a Sulfur de-nitrator works, do you have any concern or way to manage the buildup of Phosphorus? I would think that a refugium w/Chaeto would perform a nice 1-2 punch to both. Thoughts?
I use Purigen, but nothing specific for phosphates.

I think using a refugium with a macroalgae such as Chaeto is great. I didn't have success, but I'm confident my lack of success was an outlier. I would start with a refugium or marcoalgae reactor. I built a DIY macroalgae reactor using a large media reactor and LED strip.

I would first try a refugium / macroalgae reactor first. If that doesn't give you the level of nutrient export you desire, then I would try a sulfur reactor, which will definitely work.
 

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