Hanna Phosphorus ULR

[Travis Stewart]

Just picked one of these up. My first reading is 73 ppb. If I am doing it correctly, that means my phosphate value is .073 ppm? I know I want to have <0.03. Different value for phosphorus or is it converted at the same value?

 

[Jej34]

.233 is what I see from your 73ppb reading which is high.

Take your ppl reading and multiple by 3.066, then divide that number by 1000 to get your phosphate reading in Ppm

 

[mcarroll]

It's high, but don't do anything crazy if the tank is doing fine with it. If you make any changes – make them small and allow a few weeks' time between changes.

High PO4 can cause algae blooms, but it doesn't always. Aside from that, there really isn't much problem with high PO4 levels.

 

[Travis Stewart]

It's high, but don't do anything crazy if the tank is doing fine with it. If you make any changes – make them small and allow a few weeks' time between changes.

High PO4 can cause algae blooms, but it doesn't always. Aside from that, there really isn't much problem with high PO4 levels.

Thanks for the reply. I do have some very small spots of hair algae. As far as my coral, everything is booming! I do want to get rid of the hair algae but don't want to upset any coral. Do you think it would be worth getting a GFO Reactor?

 

[2una]

I've had trouble with recent reagents (like it reading double what it really is vrs ICP result)
Do a check on your RODI water & if it gives you a reading its probably telling lies
73ppb x 0.00366 is another way to do it

I tested my rodi water with the reagents i have & it tells me 34ppb
Elos high res Po4 kit on the same rodi water says hanna's telling crap

 

[fragit]

A link with conversion charts for you.... www.pny.se/aquarium

 

[Travis Stewart]

I've had trouble with recent reagents (like it reading double what it really is vrs ICP result)
Do a check on your RODI water & if it gives you a reading its probably telling lies
73ppb x 0.00366 is another way to do it

I tested my rodi water with the reagents i have & it tells me 34ppb
Elos high res Po4 kit on the same rodi water says hanna's telling ********

How doesn't RODI water contain PO4?

 

[2una]

It should be zero - but possible for other reasons like resin not changed or higher tds that its not.
That's why i checked it against the elos as it could have had po4 contaminant in it.But it doesn't.
Here's an old icp test of my (tds 0 ) rodi = 0

 

[Travis Stewart]

Anyone know why I get two different readings one after another?

I make sure to keep glass test vial clean and don't handle without paper towel.

I also make sure to get all reagent contents inside test vial and to shake for two minutes...

 

[mcarroll]

Because even when you're careful there are differences. The meter is very precise, so those differences are apparent!

That said, I don't know if you're running successive tests on one batch of water, or if you're trying to re-read the same test multiple times using the same sample and the same test along with a "control" in a second vial.

Either way you should expect some variability. Just not a lot. Technically using a "control" is bad testing since you compound your chances for there to be irrelevant differences between the test samples and associated hardware in the test number. In reality, with a fair amount of daily practice, I was able to generate very close results with either method.

 

[Travis Stewart]

Because even when you're careful there are differences. The meter is very precise, so those differences are apparent!

That said, I don't know if you're running successive tests on one batch of water, or if you're trying to re-read the same test multiple times using the same sample and the same test along with a "control" in a second vial.

Either way you should expect some variability. Just not a lot. Technically using a "control" is bad testing since you compound your chances for there to be irrelevant differences between the test samples and associated hardware in the test number. In reality, with a fair amount of daily practice, I was able to generate very close results with either method.

I have a chemistry minor so accuracy and precision are important to me. I took two different samples and made sure to rinse out vials with water I was testing. I do have some trouble at times getting all of the reagent inside the vial. Practice will only make it better I believe.

Thanks for your help!

 

[Crashjack]

I also make sure to get all reagent contents inside test vial and to shake for two minutes...

Boy, if you can open the lid, remove the sample, remove the cap, get all of the regent in the bottle, replace the cap, shake for two minutes, wipe the bottle off, re-insert the bottle, close the lid, and push the button before the checker times out and turns-off (3 minutes for some CRAZY reason), then you are doing something.

 

[Mindi]

Travis...a couple of minor suggestions on the ULR egg.
1. Dont clean the vials with paper towel or even face tissues...they are made of wood fibre and will scratch the glass eventually even if not obvious to the naked eye. Use microfibre or cotton.
2. To get all the powder reagent into the vial... I fold a 2" x 4" bit of clean paper ( I cut a stack of them from some computer paper) make a sharp fold across, then tip the powder onto the paper tapping the sachet on the paper to get out the last specks. Dry the top rim of the vial with your cotton cloth and then tip the powder in from the groove in the paper. Drying the rim stops the paper getting wet and holding up a blob of the powder. It sounds like a lot of effort but it isnt really. It gets all the powder in every time. It can all be set up before the silly 2(?) minute timer starts and switches the egg off... then you dont have that problem.

One other comment on the 936. I have demonstrated this to my own satisfaction several times... the reagent expiry dates need to be watched. I have twice tested reagent not quite expired (some months) against newly bought reagent and got significantly different results, so I just dont trust the 936 reagent once it gets within say 3-6 mths of the stamped expiry. I am sure Hanna would dispute this but it is what I have experienced....so buy small quantities of reagent more often is the way to go.

 

[skim]

I've had trouble with recent reagents (like it reading double what it really is vrs ICP result)
Do a check on your RODI water & if it gives you a reading its probably telling lies
73ppb x 0.00366 is another way to do it

I tested my rodi water with the reagents i have & it tells me 34ppb
Elos high res Po4 kit on the same rodi water says hanna's telling ********

I don't believe you can test freshwater with the Hanna ULR as it is designed for Marine use. I believe the reagent is the factor, and reacts differently in fresh water that will give a false reading. I do remember Hanna saying that it can't be used for Freshwater and is for Marine use only.