Phosphate Won’t Increase

[sundog101]

I’m trying to raise PO4 by dosing Brightwell’s NeoPhos. However I can’t seem to get the levels up. I keep getting a 0 reading with my Hanna ulr checker. The dosing spreadsheet is below. System volume is approx 110 gallons.

So, where is the phosphate going? I’m getting a little more algae growth but nothing major. Should I just keep increasing the dose until I get detectable levels?

 

[ihavecrabs]

It is likely being taken up by coral/algae/etc. I'm not familiar with Brightwell's product and how potent it is though. The quick search I did, the directions on dosage were not very clear.. quite convoluted especially with the added need to dose other products in their line haha.

Unless I missed it, I would switch to a product that specifies how many ml per gallon raises the po4.. For example, below is Seachems Flourish and the directions for "expert use" is very direct.

Formula for Seachem:
0.8*v*p=m
0.8 * volume in gallons * phosphate increase desired = ml to add in order to achieve

So if I wanted to increase my phosphate by 0.02 in a 100 gallon system, it would be: 0.8*100*0.02 = 1.6ml

 

[ajhudson15]

I have the same problem. I don't dose phosphates but I do feed real heavy and still wont come up. Will probably start dosing the flourish

 

[Justfebreezeit]

Do you have an algae scrubber or refugium?

Reason for raising phosphates?

 

[sundog101]

I have cheato in a fuge.

The phosphates are bottomed out at 0, and my corals have never done very well. On the other hand, my alk runs a little high. From what I understand higher alk and low nutrients don't mix well.

 

[cracker]

I have to dose a little myself. Be careful though it's real easy to over do it

 

[ajhudson15]

I don't have any phosphate removing material other than the tank itself. Im just trying to get it up a little bit for sps as I am not running a uln system

 

[chipmunkofdoom2]

The aragonite-based live rock we use can be ruthelessly efficient at binding phosphate. Not only does it remove phosphate from the water rather quickly, it also has a very large capacity. In one member's tests, they found that one pound of rock will bind something like 52 ppm of phosphate. No, that's not 0.052 ppm, or 52 ppb. That's 52 ppm, or 52,000 ppb.

All of the phosphate you're adding is likely getting bound to your rock.

 

[Potatohead]

Go to the store and get some TSP - Trisodium Phosphate. It's dirt cheap and a little bit (like a shockingly small amount) goes a long way. If you do a search Randy has a formula for dosing it.

 

[sundog101]

The aragonite-based live rock we use can be ruthelessly efficient at binding phosphate. Not only does it remove phosphate from the water rather quickly, it also has a very large capacity. In one member's tests, they found that one pound of rock will bind something like 52 ppm of phosphate. No, that's not 0.052 ppm, or 52 ppb. That's 52 ppm, or 52,000 ppb.

All of the phosphate you're adding is likely getting bound to your rock.

So would you just keep dosing then?

Go to the store and get some TSP - Trisodium Phosphate. It's dirt cheap and a little bit (like a shockingly small amount) goes a long way. If you do a search Randy has a formula for dosing it.

That’s what I plan on doing once I’m out of neophos.

 

[chipmunkofdoom2]

So would you just keep dosing then?

If there was a need for phosphates in my tank, yes. Why are you dosing phosphates?

 

[puffer420]

Same issue wonder if you ever figured out the issue

 

[living_tribunal]

Did you ever get to the bottom of this? I'm in a similar position and testing/dosing phosphates every day is getting unmanageable.

Kind of desperate to figure something out.

 

[Mykawl]

The aragonite-based live rock we use can be ruthelessly efficient at binding phosphate. Not only does it remove phosphate from the water rather quickly, it also has a very large capacity. In one member's tests, they found that one pound of rock will bind something like 52 ppm of phosphate. No, that's not 0.052 ppm, or 52 ppb. That's 52 ppm, or 52,000 ppb.

All of the phosphate you're adding is likely getting bound to your rock.

Super insightful does this apply to dry rock or aragonite sand as well?

 

[Randy Holmes-Farley Verified Community Expert]

Super insightful does this apply to dry rock or aragonite sand as well?

Any type of high surface area calcium carbonate that is not already coated.

 

[Randy Holmes-Farley Verified Community Expert]

Same issue wonder if you ever figured out the issue

Chipmunk gave the explanation. Dose more, if you believe your kit and the value is below where you want.

 

[living_tribunal]

Chipmunk gave the explanation. Dose more, if you believe your kit and the value is below where you want.

So the premise is to just dose and continually add daily phosphates until the rock has absorbed all that it can and then we can get back on a normal routine?

 

[Mykawl]

Adding to the above there other elements besides phosphates rocks or sand should be “loaded” with?

 

[Randy Holmes-Farley Verified Community Expert]

So the premise is to just dose and continually add daily phosphates until the rock has absorbed all that it can and then we can get back on a normal routine?

Well, the amount bound depends entirely on the concentration in the water, but with that caveat, yes. If it is stable at 0.01 ppm phosphate and you want to boost it to 0.02 ppm, then more will bind to the rock.

 

[Randy Holmes-Farley Verified Community Expert]

Adding to the above there other elements besides phosphates rocks or sand should be “loaded” with?

New calcium carbonate can bind organics, magnesium, calcium and carbonate. Certainly many trace metals too, but that is more complicated to assess as they are mostly bound to organics already.