Hannah Phosphate checker issue?

[Arkayology]

I have had my hannah meter for about 2 years now and I have always gotten a range of results when measuring my phos. For example, yesterday I measured my phosphate 5 times and received the following results in order: 0.06, 0.03, 0.0, 0.0. 0.0.

I am not sure what to make of this. I follow the directions word for word. Does it need to be checked against a standard? I have tried to find a hannah check solution online to no avail.

[djsmallz]

There is a slight margin for error and I believe you fall into its place.

[Arkayology]

There is a slight margin for error and I believe you fall into its place.

Bah, so I should take an average of these results then to get an "accurate" reading?

0.9/5=0.018ppm phos

[djsmallz]

Yes, you can do that I always double or triple check mine, that darn powder sometimes gets on my nerves as you never really know if you got it all...lol

[TimeConsumer]

My process with the Hannah checker is as follows:

1) Clean the cuvette inside and out with RO/DI water
2) Fill using a syringe to 10ml, don't trust the mark on the cuvette
3) Prepare your reagent pack in advance. I like to cut mine in half diagonally, and spread the sides until I have a diamond shape, to funnel it in
4) When doing the reference check and the test, have the cuvette facing the same direction
5) Do not touch the cuvette with your hands, I use a lint-free telescope cleaning cloth
6) After the reference check is completed, start a timer, as the checker will turn off automatically after 2 minutes
7) Open the cuvette, fill with the reagent, and begin to mix
8) Right before the 2 minute timer is up, press and hold the button on the checker until a 3 minute timer starts, continue to mix
9) With about a minute to spare, place the cuvette in the checker (facing the same direction) and let it settle for a minute before it takes the reading

I found this method to take a little longer, but produce much more accurate and precise results.

[shifty51008]

The checker has a +/- of. 03 so your in that range. With your results i would say you have. 03 po4

[outssider]

My process with the Hannah checker is as follows:

1) Clean the cuvette inside and out with RO/DI water
2) Fill using a syringe to 10ml, don't trust the mark on the cuvette
3) Prepare your reagent pack in advance. I like to cut mine in half diagonally, and spread the sides until I have a diamond shape, to funnel it in
4) When doing the reference check and the test, have the cuvette facing the same direction
5) Do not touch the cuvette with your hands, I use a lint-free telescope cleaning cloth
6) After the reference check is completed, start a timer, as the checker will turn off automatically after 2 minutes
7) Open the cuvette, fill with the reagent, and begin to mix
8) Right before the 2 minute timer is up, press and hold the button on the checker until a 3 minute timer starts, continue to mix
9) With about a minute to spare, place the cuvette in the checker (facing the same direction) and let it settle for a minute before it takes the reading

I found this method to take a little longer, but produce much more accurate and precise results.

this is almost exactly what I do except for 2 things.

1...I can get mine disolved in two minutes so I let the vial sit in the checker for 3 minutes to settle.

2...I fill the other vial with tank water and double check my original results using the two vial method a few times. all readings should be pretty close to one another...within the margin of error