According to sources, the amount of KH2PO4 to add after a major water
change is 1/16-1/8 teaspoon. When using the Fleet Enema method, are
my calculations correct?

According to the package, each 188ml bottle contains 19g of MonoBasic
Sodium Phosphate and 7g of DiBasic Sodium Phosphate. That is 26g of
total available KH2PO4.

That works out to 2ml of solution roughly equivalent to 1/10th
teaspoon of pure KH2PO4 - right?

1/10 teaspoon in 75 gal - 1.18ppm
2ml of enema in 75 gal = 1.08ppm

Is this correct or am I an idiot?!

Thanks,
Greg

On Thu, 19 Jun 2003 23:26:51 -0400, Greg
wrote:

Correction Below!!!

According to sources, the amount of KH2PO4 to add after a major water
change is 1/16-1/8 teaspoon. When using the Fleet Enema method, are
my calculations correct?

According to the package, each 188ml bottle contains 19g of MonoBasic
Sodium Phosphate and 7g of DiBasic Sodium Phosphate. That is 26g of
total available KH2PO4.

That would be 118 ml NOT 188 ml.... Stupid Typo...

That works out to 2ml of solution roughly equivalent to 1/10th
teaspoon of pure KH2PO4 - right?

1/10 teaspoon in 75 gal - 1.18ppm
2ml of enema in 75 gal = 1.08ppm

Is this correct or am I an idiot?!

Thanks,
Greg

On Thu, 19 Jun 2003 23:26:51 -0400, Greg
wrote:

1/10 teaspoon in 75 gal - 1.18ppm
2ml of enema in 75 gal = 1.08ppm

Is this correct or am I an idiot?!

Short answer: Yes, this is correct.

Long Answer:

Well, I've never dosed phosphate using the fleet enema, but here's
some calculations I did for someone who emailed me with a similar
question.

Note: The person who I was emailing had said that the Fleet enema
contained 118ml of solution containing 16 grams of monobasic sodium
phosphate and 7 grams of dibasic sodium phosphate. This is slightly
different than your statement of 19g and 7g. Which is correct?
You'll need to adjust the calcs below if the 19g is correct instead of
the 16g.

-------------

monobasic sodium phosphate
Molecular formula: H2NaPO4

dibasic sodium phosphate
Molecular formula: HNa2PO4


The molecular weights involved a
H : 1.00794 g/mol
Na : 22.98977 g/mol
P : 30.97376 g/mol
O : 15.9994 g/mol

(monobasic sodium phosphate)
H2NaPO4 = 2 hygrogens, 1 sodium, 1 phosphorus, 4 oxygen.

when you add it up, 1 mol of H2NaPO4 = 119.977g. Phosphate (PO4) =
94.97136 g/mol. So, 79% of the weight of H2NaPO4 is phosphate.

(dibasic sodium phosphate)
HNaPO4 is almost the same, just missing one hydrogen
1 Hydrogen, 1 sodium, 1 phosphorus, 4 oxygen.

1 mol of HNaPO4 = 118.9691g. So, 80% of HNaPO4 is phosphate.

118ml, containing 16 grams of monobasic, and 7 grams of dibasic.

So, in 118ml, you have 12.64g of phosphate from the monobasic,
and 5.6g of phosphate from dibasic. (79% and 80%).

So, in 118ml, you have 18.24g of phosphate.

Each ml would then contain 0.155g of phosphate, or 155mg.

---------------------------------------

So, to find out if 2ml of enema in 75 gal = 1.08ppm:

2ml would be 310mg. 310mg of potassium in 283 liters = 1.09 mg/l or
1.09ppm.

And yes, 1/10 of a teaspoon in a 75g would be 1.18ppm.





Chuck Gadd
http://www.csd.net/~cgadd/aqua

A quick disclaimer: Be sure to check this over before dumping stuff
into your tank. To be completely honest, I should mention that I
failed chemistry back in high-school.




Chuck Gadd
http://www.csd.net/~cgadd/aqua

On Thu, 19 Jun 2003 23:26:51 -0400, Greg
wrote:

1/10 teaspoon in 75 gal - 1.18ppm
2ml of enema in 75 gal = 1.08ppm

Is this correct or am I an idiot?!

Short answer: Yes, this is correct.

Long Answer:

Well, I've never dosed phosphate using the fleet enema, but here's
some calculations I did for someone who emailed me with a similar
question.

Note: The person who I was emailing had said that the Fleet enema
contained 118ml of solution containing 16 grams of monobasic sodium
phosphate and 7 grams of dibasic sodium phosphate. This is slightly
different than your statement of 19g and 7g. Which is correct?
You'll need to adjust the calcs below if the 19g is correct instead of
the 16g.

-------------

monobasic sodium phosphate
Molecular formula: H2NaPO4

dibasic sodium phosphate
Molecular formula: HNa2PO4


The molecular weights involved a
H : 1.00794 g/mol
Na : 22.98977 g/mol
P : 30.97376 g/mol
O : 15.9994 g/mol

(monobasic sodium phosphate)
H2NaPO4 = 2 hygrogens, 1 sodium, 1 phosphorus, 4 oxygen.

when you add it up, 1 mol of H2NaPO4 = 119.977g. Phosphate (PO4) =
94.97136 g/mol. So, 79% of the weight of H2NaPO4 is phosphate.

(dibasic sodium phosphate)
HNaPO4 is almost the same, just missing one hydrogen
1 Hydrogen, 1 sodium, 1 phosphorus, 4 oxygen.

1 mol of HNaPO4 = 118.9691g. So, 80% of HNaPO4 is phosphate.

118ml, containing 16 grams of monobasic, and 7 grams of dibasic.

So, in 118ml, you have 12.64g of phosphate from the monobasic,
and 5.6g of phosphate from dibasic. (79% and 80%).

So, in 118ml, you have 18.24g of phosphate.

Each ml would then contain 0.155g of phosphate, or 155mg.

---------------------------------------

So, to find out if 2ml of enema in 75 gal = 1.08ppm:

2ml would be 310mg. 310mg of potassium in 283 liters = 1.09 mg/l or
1.09ppm.

And yes, 1/10 of a teaspoon in a 75g would be 1.18ppm.





Chuck Gadd
http://www.csd.net/~cgadd/aqua

A quick disclaimer: Be sure to check this over before dumping stuff
into your tank. To be completely honest, I should mention that I
failed chemistry back in high-school.




Chuck Gadd
http://www.csd.net/~cgadd/aqua

One thing to keep in mind,
Unless you are measuring uptake rate, near zero, research etc "close"
is more than good enough.

Traces, K+, PO4 are fairly robust and their precise control within a
narrow range is simply uncalled for to keep a nice planted tank.
Running out, extreme excess can/may cause issues.
But if you have a 2-3 days supply, in most cases you are fine.

You'll find little difference if you add 1ppm once a week or 0.5ppm 2x
a week.

Will one ppm NO3 make or break any tank set up? Only if it's 1ppm vs
0ppm or on the upper range of 20+ppm etc.
Regards,
Tom Barr

On Thu, 19 Jun 2003 23:19:22 -0600, Chuck Gadd wrote:

A quick disclaimer: Be sure to check this over before dumping stuff
into your tank. To be completely honest, I should mention that I
failed chemistry back in high-school.

I didn't, but it was a LOOOONG time ago... ;-)

I REALLY appreciate the facts, figures and formulas. The reason for
the 16/19mg difference is that the 'Fleet' enema is not actually made
by Fleet, it's made by NutraMax Products of Gloucester, MA.

And for a good laugh, you should have seen the look on my
better-half's face when I began dumping a strange concoction made up
of Stump Killer, NoSalt, and Enemas into the huge aquarium full of
fish that we have had for over a year...

Surely, she quietly believes I am completely nuts!

Greg

http://videodoc.home.mindspring.com

And for a good laugh, you should have seen the look on my
better-half's face when I began dumping a strange concoction made up
of Stump Killer, NoSalt, and Enemas into the huge aquarium full of
fish that we have had for over a year...

Surely, she quietly believes I am completely nuts!

Greg


Greg I know that reaction you are speaking of, my girlfriend just shakes her
head anymore. But she loves the way the tank looks so I guess it's all
good...

Ron

Greg wrote in message . ..
On Thu, 19 Jun 2003 23:19:22 -0600, Chuck Gadd wrote:

A quick disclaimer: Be sure to check this over before dumping stuff
into your tank. To be completely honest, I should mention that I
failed chemistry back in high-school.

I didn't, but it was a LOOOONG time ago... ;-)

I REALLY appreciate the facts, figures and formulas. The reason for
the 16/19mg difference is that the 'Fleet' enema is not actually made
by Fleet, it's made by NutraMax Products of Gloucester, MA.

And for a good laugh, you should have seen the look on my
better-half's face when I began dumping a strange concoction made up
of Stump Killer, NoSalt, and Enemas into the huge aquarium full of
fish that we have had for over a year...

Surely, she quietly believes I am completely nuts!

Greg

http://videodoc.home.mindspring.com

Like my other half says about me, she is right
Regards,
Tom Barr

Chuck,

FWIW, I dose PO4 from the The Walmart equate brand knock off of the Fleet
enema...19g of Monobasic Sodium Phosphate and 7g of Dibasic Sodium
Phosphate in a 133 ml solution. Not sure if that helped or hurt?

DJay


"Chuck Gadd" wrote in message
...
On Thu, 19 Jun 2003 23:26:51 -0400, Greg
wrote:

1/10 teaspoon in 75 gal - 1.18ppm
2ml of enema in 75 gal = 1.08ppm

Is this correct or am I an idiot?!

Short answer: Yes, this is correct.

Long Answer:

Well, I've never dosed phosphate using the fleet enema, but here's
some calculations I did for someone who emailed me with a similar
question.

Note: The person who I was emailing had said that the Fleet enema
contained 118ml of solution containing 16 grams of monobasic sodium
phosphate and 7 grams of dibasic sodium phosphate. This is slightly
different than your statement of 19g and 7g. Which is correct?
You'll need to adjust the calcs below if the 19g is correct instead of
the 16g.

-------------

monobasic sodium phosphate
Molecular formula: H2NaPO4

dibasic sodium phosphate
Molecular formula: HNa2PO4


The molecular weights involved a
H : 1.00794 g/mol
Na : 22.98977 g/mol
P : 30.97376 g/mol
O : 15.9994 g/mol

(monobasic sodium phosphate)
H2NaPO4 = 2 hygrogens, 1 sodium, 1 phosphorus, 4 oxygen.

when you add it up, 1 mol of H2NaPO4 = 119.977g. Phosphate (PO4) =
94.97136 g/mol. So, 79% of the weight of H2NaPO4 is phosphate.

(dibasic sodium phosphate)
HNaPO4 is almost the same, just missing one hydrogen
1 Hydrogen, 1 sodium, 1 phosphorus, 4 oxygen.

1 mol of HNaPO4 = 118.9691g. So, 80% of HNaPO4 is phosphate.

118ml, containing 16 grams of monobasic, and 7 grams of dibasic.

So, in 118ml, you have 12.64g of phosphate from the monobasic,
and 5.6g of phosphate from dibasic. (79% and 80%).

So, in 118ml, you have 18.24g of phosphate.

Each ml would then contain 0.155g of phosphate, or 155mg.

---------------------------------------

So, to find out if 2ml of enema in 75 gal = 1.08ppm:

2ml would be 310mg. 310mg of potassium in 283 liters = 1.09 mg/l or
1.09ppm.

And yes, 1/10 of a teaspoon in a 75g would be 1.18ppm.





Chuck Gadd
http://www.csd.net/~cgadd/aqua

Greg wrote:

you should have seen the look on my better-half's face
when I began dumping a strange concoction made up of
Stump Killer, NoSalt, and Enemas into the huge aquarium
full of fish that we have had for over a year...

Consider the possibility that the main reason she keeps you around is
for the unpredictable entertainment value you provide. I'm pretty sure
that's why my wife keeps me. Well, that, and I do laundry.



--
www.ericschreiber.com