Red field ratio?

[Fishingandreefing]

Question on the red field ratio. So 15 nitrate and .10 phosphate would be good ratio? My current nitrate is at 12 and phosphate is 16. My plan is to raise nitrate and I have read that phosphate might drop? If not, I will use lanthanum chloride to drop it.

on my other more matured tank, my nitrate is 15 but phosphate is .35. My plan is to raise phosphate to 20 and drop phosphate close to .15. I really don’t want to drop it too much for possible negative side.

comment or suggestions?

 

[redfishbluefish]

First off, is there a decimal error with phosphate? A phosphate of 16, you'd be able to chew it!

As far as the Redfield ratio, don't be overly concerned with the number....it is from a specific algae found in some specific ocean. And it's actually C:N.

Simply start reducing your numbers and see where you end up. Pick some way to reduce these two guys and go for it.....skimming, water changes, carbon dosing, refugium, algae scrubber, etc.

 

[Fishingandreefing]

First off, is there a decimal error with phosphate? A phosphate of 16, you'd be able to chew it!

As far as the Redfield ratio, don't be overly concerned with the number....it is from a specific algae found in some specific ocean. And it's actually C:N.

Simply start reducing your numbers and see where you end up. Pick some way to reduce these two guys and go for it.....skimming, water changes, carbon dosing, refugium, algae scrubber, etc.

Yup, def typo .16

 

[Fishingandreefing]

Yup, def typo .16

I know my phosphate is stemming from my dry rocks I put in way back. I guess I am just slowly dosing LC to a point that the rocks all leached out and exhausted the phosphate

my phosphate was .90 two years ago and I dropped it down to .30 by LC. However, every time I tried to drop it lower and it always comes back to around .3

 

[Randy Holmes-Farley Verified Community Expert]

Redfield ratio is an experimental observation in the ocean that, IMO, is of zero value for setting target levels in reef tanks.

There's no justification for a ratio as a target in a reef tank, Redfield or otherwise. Challenge anyone suggesting otherwise to suggest what is useful about it, as opposed to setting absolute target levels.

Instead of a ratio, which, for example, might suggest that if nitrate is 10,000 ppm, phosphate should be over 1,000 ppm. Or if N is 0.0000001 ppm, phosphate should be 0.000001 ppm.

Instead, it makes all the sense in the world to set actual target values for N and P in a reef tanks.

Say, 2 to 10 ppm nitrate and 0.02 to 0.1 ppm phosphate. Or something like that. Any description like that is going to be more useful than a fixed ratio independent of the actual values.

 

[Fishingandreefing]

Redfield ratio is an experimental observation in the ocean that, IMO, is of zero value for setting target levels in reef tanks.

There's no justification for a ratio as a target in a reef tank, Redfield or otherwise. Challenge anyone suggesting otherwise to suggest what is useful about it, as opposed to setting absolute target levels.

Instead of a ratio, which, for example, might suggest that if nitrate is 10,000 ppm, phosphate should be over 1,000 ppm. Or if N is 0.0000001 ppm, phosphate should be 0.000001 ppm.

Instead, it makes all the sense in the world to set actual target values for N and P in a reef tanks.

Say, 2 to 10 ppm nitrate and 0.02 to 0.1 ppm phosphate. Or something like that. Any description like that is going to be more useful than a fixed ratio independent of the actual values.

So you’re saying 10 nitrate and .10 phosphate. Only reason I am going that direction was that my corals to include my trachy was closed up or doesn’t open all the way like used to for almost 6 months! (Nitrate 7.8 and phosphate 15).

I then dosed neonitro and mb7 bumped up to 12, then my trachy all the sudden opened up 95%. I was like wow!

 

[Randy Holmes-Farley Verified Community Expert]

There is no magic set of numbers.

I gave a range for each. IMO, this is a reasonable set of targets, with higher than the range better than lower for each:

2 to 10 ppm nitrate
0.02 to 0.1 ppm phosphate

 

[Fishingandreefing]

There is no magic set of numbers.

I gave a range for each. IMO, this is a reasonable set of targets, with higher than the range better than lower for each:

2 to 10 ppm nitrate
0.02 to 0.1 ppm phosphate

But it seems nitrates need to be higher than phosphate works

 

[Randy Holmes-Farley Verified Community Expert]

But it seems nitrates need to be higher than phosphate works

Unless there is another source of N that is readily available in the tank, yes, target ranges for nitrate are always much higher than phosphate.

 

[Fishingandreefing]

Unless there is another source of N that is readily available in the tank, yes, target ranges for nitrate are always much higher than phosphate.

Great. Thx