Is there an ULR Phosphate/Phosphorous test that isn't based on jenky packets of powder?

[PacoPetty]

I think many of us are with you, I hate those little packets! You could buy yourself one of those tiny glass lab funnels on ebay or Amazon, that might help keep you from spilling the powder. I have some that I use mixing Ceramic coating, sort of like these; clicky

I absolutely hate the packets of powder! What a brilliant idea to buy the glass funnel. I am checking Amazon now! Thank you!

 

[PacoPetty]

I absolutely hate the packets of powder! What a brilliant idea to buy the glass funnel. I am checking Amazon now! Thank you!

I just bought a set of 5 glass funnels from 35 mm to 75 mm on Amazon for $11.59!

 

[ianryd]

Does anybody know what the hannah powder is? Could we buy it in a vile somewhere? Scoop our own?

 

[Flux Capacitor]

Wait so are you suppose to wait the full 3 minutes or not?

This is my process:
1. Fill vial (a) with RO water
2. Fill vial (b) with tank water
3. Add reagent to vial (b)
4. Shake vial (b) for 2 minutes
5. Press checker button
6. Add vial (a)
7. Press checker button
8. Add vial (b)
9. Hold checker button
10. Wait 3 minutes.

Has anyone checked right after shaking and then at 3 minutes? Because I've noticed my tests results decrease when I retest after 3 minutes.
For example, 3:00- 44, 3:20- 35, 3:40- 25, 4:00- 7, 4:20- 0. Everytime I've retested the reading is always lower.

You aren’t suppose to use RO water to zero the checker, it should be tank water.

 

[Randy Holmes-Farley]

Does anybody know what the hannah powder is? Could we buy it in a vile somewhere? Scoop our own?

Unlikely to be cheaper and certainly not easier to measure out.

 

[ahiggins]

It’s definitely my most neglected test.

I agree. I only ever test phos if I’m working on an algae issue or when I had dinos.

 

[Cell]

I wonder if the packets could be reconstituted in RODI or some other buffer and stored on the shelf for awhile. I assume not or else why wouldn't they sell it as a solution already, but who knows.

Alternatively has anyone tried pipetting 1 mL of water into the packet itself, aspirate it a bit, then transfer to the vial?

 

[taricha]

I wonder if the packets could be reconstituted in RODI or some other buffer and stored on the shelf for awhile. I assume not or else why wouldn't they sell it as a solution already, but who knows.

Alternatively has anyone tried pipetting 1 mL of water into the packet itself, aspirate it a bit, then transfer to the vial?

not soluble very quickly. Don't see how wetting the packet/solids will help.
If people hate getting the powder into the tiny mouth glass vial, you can just react the powder and 10mL of sample water in any clean, sealable nonreactive container, and it'll go fine. Then transfer enough reacted liquid back into the hanna cuvette for the final check.

 

[Randy Holmes-Farley]

I wonder if the packets could be reconstituted in RODI or some other buffer and stored on the shelf for awhile. I assume not or else why wouldn't they sell it as a solution already, but who knows.

Who knows? Confuscious says:

“He Who Knows And Knows That He Knows Is A Wise Man - Follow Him;
He Who Knows Not And Knows Not That He Knows Not Is A Fool - Shun Him”

In this case, I guess I'm wise.

The solution is unstable.

from the EPA web site discussing this method (ascorbic acid method for phosphate)

https://www.epa.gov/sites/production/files/2015-08/documents/method_365-1_1993.pdf

" This volume is sufficient for a four hour operation. Since the stability of this solution is limited, it must be freshly prepared for each run "

They also say it can be modified to make it more stable, but this is not a DIY alteration of the already-mixed Hanna packets:

" Note: A stable solution can be prepared by not including the ascorbic acid in the combined reagent. If this is done, the mixed reagent (molybdate, tartrate, and acid) is pumped through the distilled water line and the ascorbic acid solution (30 mL of 7.5 diluted to 100 mL with reagent water) through the original mixed reagent line. "

 

[jccaclimber]

Does that mean it could be a liquid test if two different liquids were used, or are they not both shelf stable?

 

[Cell]

Why dont they put the powder in a vial and give a scoop like Salifert uses for its Ca+ test?

 

[Fishingandreefing]

I really don't understand why people have so much trouble with these. If you shake it, then cut along the lines, then fold it (hard to describe), it creates a perfect funnel and gets everything.

I wouldn't be opposed to having another LR test, just my thoughts on the matter.

EDIT: Like this!

I didn’t read the entire threat and I am not that old either to a point where things are not as easy as it sounds sometimes when you’re old or not as stable with your hands.

 

[Randy Holmes-Farley]

Does that mean it could be a liquid test if two different liquids were used, or are they not both shelf stable?

I think folks are trying to reinvent the wheel. lol

Ascorbic acid is critical for this method and it oxidizes in air. That (and light degradation) is a main reason for packets that multiple companies use.

From the link above:

" Ascorbic acid, 0.1M: Dissolve 1.8 g of ascorbic acid (CASRN 50-81-7) in 100 mL of reagent water. The solution is stable for about a week if prepared with water containing no more than trace amounts of heavy metals and stored at 4°C "

Ascorbic Acid - The Chemical Company

TCC’s Ascorbic Acid is a naturally occurring organic compound with antioxidant properties. It is a white solid, but impure samples can appear yellowish. It dissolves well in water to give mildly acidic solutions. Ascorbic acid is one form of vitamin C. Ascorbic acid is found in plants...

thechemco.com

.

" As a mild reducing agent, ascorbic acid degrades upon exposure to air, converting the oxygen to water. The redox reaction is accelerated by the presence of metal ions and light. It can be oxidized by one electron to a radical state or doubly oxidized to the stable form called dehydroascorbic acid. "

 

[Randy Holmes-Farley]

Why dont they put the powder in a vial and give a scoop like Salifert uses for its Ca+ test?

lol

Because the chemistry is different, and not stable to air.

Hanna is not the only company using packets.

Hach, likely the top name in test kits for professionals, has used phosphate packets for decades. I used them back in the last century. lol

PhosVer® 3 Phosphate Reagent Powder Pillows, 10 mL, pk/100

PhosVer® 3 Phosphate Reagent Powder Pillows, 10 mL, pk/100

www.hach.com

 

[taricha]

also if you think pouring a packet into the vial is tricky, try emptying a scoop into that small opening.

 

[WiscoFishNut]

So I tried out a new PO4 test kit from Tropic Marin over the weekend. Ease of use = perfect. 2 liquid reagents to use and a simple color match to determine levels. The test only measures ULR, so I'll have to wait till my PO4 gets knocked down a bit(greater than 1.0 right now) to see how easy it is to read in those lower ranges.

 

[Randy Holmes-Farley]

The test only measures ULR, so I'll have to wait till my PO4 gets knocked down a bit(greater than 1.0 right now) to see how easy it is toe read in those lower ranges.

I don't think most folks think of 1.0 ppm phosphate as ultra low. lol