Phosphate Hi - Nitrate Lo

[Klyph]

I’ve searched recent threads and can’t find one that gets to the heart of my question.

my specific situation: I have a 150 gallon Red Sea Reefer. I’m running an AI Prime fuge and a Red Sea skimmer. All my parameters are in the sweet spots, with alk around 8.5, ph 8.3, salinity 1.024, temp 79, calc 440, mg 1300.

my phosphates hover around .01-.05, using the ultra low Hanna checker. My nitrates are around 15, which is much higher than it seems like it should be.

I’ve read numerous times that nitrates and phosphates should have a ratio of roughly 16 to 1. I understand that is a loose rule, and shouldn’t be taken too seriously, but I does beg the obvious question...

Do filtration techniques all filter phosphate and nitrate evenly? My assumption is no, and if they don’t, what are the differences? For example, if skimmers pull out phosphate quicker than nitrate, I could reduce my use of the skimmer to get them more in balance.

@Randy Holmes-Farley , could you share your knowledge on how different filtration techniques effect phosphate vs nitrate?

 

[Spare time]

I would ignore that ratio. I don't think it has any implication in our tanks. What settings do you have on the AI fuge light?

I also want to add that 0.05 and 0.1ppm is fine for phosphates and 15ppm is fine for nitrate. You shouldn't major have issues with that.

 

[Klyph]

Fuge light - AI Prime Fuge light, running at 60% for 6 hours at night.
I get the ratio isn’t critical, but it seems like my filtration is doing a MUCH better job removing phosphate, than it is nitrate.

my real question is, do certain filtration tools work better for phosphates vs nitrates?

 

[Adamantium]

Everything sounds fine to me. Water changes are your best bet for nitrates, though yours aren’t unreasonably high.

The Redfield Ratio is the 16:1 you’ve heard about. It’s generally shown to not be important for reef tanks. It’s just what the levels are in the ocean, generally speaking.

I think you got the title backwards, btw.

 

[Klyph]

...another related question... do certain inputs (e.g. frozen food, nori, phytoplankton, amino acids, trace elements, etc.) increase phosphates more than nitrates, or vice versa?

 

[Klyph]

Everything sounds fine to me. Water changes are your best bet for nitrates.

I think you got the title backwards, btw.

I did get the title wrong. I’ll try and fix that. I’m still more interested in input and uptake, and how to manipulate phosphates and nitrates distinctly.

 

[Spare time]

Fuge light - AI Prime Fuge light, running at 60% for 6 hours at night.
I get the ratio isn’t critical, but it seems like my filtration is doing a MUCH better job removing phosphate, than it is nitrate.

my real question is, do certain filtration tools work better for phosphates vs nitrates?

You can crank up the refugium light power or length. That should handle nitrates and phosphates very well.

Some things handle nitrates far better than phosphates. This is true for carbon dosing and biopellets. Some filter medias, such as gfo, only reduce phosphate and the reverse also applies to nitrate filter pads. Nothing removes them evenly.

 

[Spare time]

...another related question... do certain inputs (e.g. frozen food, nori, phytoplankton, amino acids, trace elements, etc.) increase phosphates more than nitrates, or vice versa?

Trace elements do not raise nitrate or phosphate but can aid in macroalgae growth which removed both. Aminos are strictly nitrogen, no phosphorus at all. Certain foods have higher phosphorus content than others. Live phyto shouldn't add any waste.

 

[Klyph]

Trace elements do not raise nitrate or phosphate but can aid in macroalgae growth which removed both. Aminos are strictly nitrogen, no phosphorus at all. Certain foods have higher phosphorus content than others. Live phyto shouldn't add

You can crank up the refugium light power or length. That should handle nitrates and phosphates very well.

Some things handle nitrates far better than phosphates. This is true for carbon dosing and biopellets. Some filter medias, such as gfo, only reduce phosphate and the reverse also applies to nitrate filter pads. Nothing removes them evenly.

@Spare time , thanks for the response. Does the protein skimmer do a better job with phosphate or nitrate? Same question for the refugium?

 

[Klyph]

You can crank up the refugium light power or length. That should handle nitrates and phosphates very well.

Some things handle nitrates far better than phosphates. This is true for carbon dosing and biopellets. Some filter medias, such as gfo, only reduce phosphate and the reverse also applies to nitrate filter pads. Nothing removes them evenly.

@Spare time , thanks for the response. Does the protein skimmer do a better job with phosphate or nitrate? Same question for the refugium?

 

[Spare time]

@Spare time , thanks for the response. Does the protein skimmer do a better job with phosphate or nitrate? Same question for the refugium?

For protein skimmer, I honestly am not sure but my educated guess would be better at nitrates (though it helps prevent both). Refugiums think would use slightly more nitrate but again this is a guess.

 

[Rmckoy]

@Spare time , thanks for the response. Does the protein skimmer do a better job with phosphate or nitrate? Same question for the refugium?

The way I understood it from day 1

the skimmer removes organics that are suspended in the water column .
prior to decomposing which changes to ammonia which in turn transforms to nitrates .

I might be wrong . That’s how I understand it

 

[Randy Holmes-Farley Verified Community Expert]

Phosphate also comes from organic breakdown and skimmers also help with it.

I do not see any problem with the current values of 0.01 to 0.05 ppm phosphate and nitrate at 15 ppm. If the phosphate was regularly 0.01 ppm, I'd boost it by feeding more or dosing it.

 

[Pistondog]

I did get the title wrong. I’ll try and fix that. I’m still more interested in input and uptake, and how to manipulate phosphates and nitrates distinctly.

Reef roids is mostly phosphate.