# Ammonium Phosphate



## furballi (Feb 2, 2007)

Don't see many posts about the use of ammonium phosphate as macro nutrient. I used to dose with ammonium phosphate when I had my 20 gal with just a few fish. A 5 lb box of "triple phosphate" can be found at the local nursery for about $6. 

Ammonium phosphate is more soluble in water and can quickly be absorbed by plants. It is often labeled as 0-45-0.


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## mrbelvedere138 (Jan 18, 2006)

What I'm wondering is what the N-P ratio ends up being. How many usable atoms of nitrogen and phosphorous can plants glean? Any chemistry experts? 

Where's Salt when you need him (possibly her)?


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## furballi (Feb 2, 2007)

As I recalled from chemistry, ammonium phosphate is (NH4)3PO4 with approximately 150 g/mol. N is 14, and H is 1.


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## hoppycalif (Apr 7, 2005)

In my opinion it is a good rule to try to keep ammonium or ammonia out of the water. Adding it could easily trigger an algae bloom. It makes a lot more sense to use KNO3, which also supplies needed potassium and does not start an algae bloom.


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## dennis (Mar 1, 2004)

> It is often labeled as 0-45-0.


Actually, that should be labeled as 28-45-0 as it is 28%N.

mrbelvedere- Nitrogen weights 14.001 g/mol. (NH4)3PO4 weights 149.07g/mol. So, N in (NH4)3PO4 is (14.001*3)/149.07= 28.18%. Phosphorus weights 30.974g/mol so 30.974/149.07= 20.78% P in (NH4)3PO4. So, N ratio is 28.18:20.78 or 1.36:1. As a comparison, N in NO3O4 is 22.58:32.61 or 1:1.44.

And really for fun, if you add 1gram of (NH4)3PO4 to 100liters of water:
1g (NH4)3PO4= .2818g N => 281.8mg/100l=> 2.818mg/l N (equivalent to 12.4mg/l NO3)
1g (NH4)3PO4= .2078g P => 207.8mg/100l=> 2.078mg/l P (equivalent to 6.37mg/l PO4) [also, you can figure this by PO4 weights 94.972g/mol or 63.71% PO4. So, 1g (NH4)3PO4 has .6371g PO4=> 637.1mg/100l= 6.37mg/l PO4]

Therefor, if you wanted to add the equivalent of 4mg/l NO3 (or .91mg/l N) using this stuff, you would also add with it 2.05mg/l PO4. A little high for my tastes but not horrible. Keep in mind though I would not add that much N in the form of NH4 all at once. I would think you would want to add no more than 1/4 or 1/2 that at a time.


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## Squawkbert (Jan 3, 2007)

So, to summ it up, too much PO4, NH3/NH4 not as good as NO3.


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## rugie (Mar 16, 2007)

Not surprising you do not see many posts on this subject--It is not recommended for show tanks especially one that contains animals. the plant growers force feed the stuff to their stock, (along with other nutrients) to get max growth.


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## essabee (Oct 11, 2006)

furballi said:


> Don't see many posts about the use of ammonium phosphate as macro nutrient. I used to dose with ammonium phosphate when I had my 20 gal with just a few fish. A 5 lb box of "triple phosphate" can be found at the local nursery for about $6.
> 
> Ammonium phosphate is more soluble in water and can quickly be absorbed by plants. It is often labeled as 0-45-0.


Am I wrong or "triple phosphate" is "triple super phosphate" an agricultural fertiliser containing commercial calcium phosphate and therefore 0:45:0 NPK lable. Again in NPK terminology the content of phosphorous in given as percentage of P2O5 and not as P. So "single super phosphate" a 1:2 mixture of calcium phosphate and calcium sulphate is shown as 0:16:0; "double super phosphate", 1:1mixture is 0:30:0 and the triple is 0:45:0.


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