help with Hanna phosphate checker

[Magickiwi]

Originally Posted by lastlight

if that's the case and we can't assume that two seemingly identical vials are the same to the meter then perhaps even inserting the same vial back into it but rotating it differently could be a factor too.

Bingo... Which is why the Hanna colorimeters for phosphate get such bad reviews. They are a pretty flawed method if two different vials, etc. interfere with the reliable results. And having an auto-off of three minutes when simply mixing the reagent takes a minimum of two was just poor planning...

[mark]

you can compare the vials by doing a "test" using each with ro, no reagent. I've ran it a couple of times, different order and always get zero.

[lastlight]

Originally Posted by mark

you can compare the vials by doing a "test" using each with ro, no reagent. I've ran it a couple of times, different order and always get zero.

so you zero with one vial and have the other mixed?

why else would they give us two lol?

[Reef Pilot]

Geez guys, it is really not that hard... I only use one vial, and always get it completely mixed every time. Like I said, just have to do it right as described above, and it is then very accurate and consistent.

[lastlight]

Originally Posted by Reef Pilot

Geez guys, it is really not that hard... I only use one vial, and always get it completely mixed every time. Like I said, just have to do it right as described above, and it is then very accurate and consistent.

my readings sometimes vary so it's good conversation to me. if there's ways to make the process more accurate it's worth discussing.

[straightrazorguy]

Originally Posted by Reef Pilot

Geez guys, it is really not that hard... I only use one vial, and always get it completely mixed every time. Like I said, just have to do it right as described above, and it is then very accurate and consistent.

Maybe I'm slow, but I cannot fill vial, add ALL the reagent in the pouch, and completely mix it in 3 min. At the end of 3 min I still have solid particles of reagent swirling in the vial. I don't want to measure it unless it's completely dissolved. That's why I use 2 vials.

[Reef Pilot]

Originally Posted by straightrazorguy

Maybe I'm slow, but I cannot fill vial, add ALL the reagent in the pouch, and completely mix it in 3 min. At the end of 3 min I still have solid particles of reagent swirling in the vial. I don't want to measure it unless it's completely dissolved. That's why I use 2 vials.

What do you mean fill the vial?? That is done at the beginning before C1. I also have the packet cut, funnel formed and ready to pour before the 3 min time limit begins. I usually use close to the full 3 min before pressing (and holding) C2, but have no trouble completely dissolving the powder.

[mark]

Originally Posted by lastlight

so you zero with one vial and have the other mixed?

why else would they give us two lol?

when I started and was slow with the Hanna was using both vials. Now do the C1, add reagent, shake, hold the button to get the 3 minute timer started then done. Seen a video where you crease the packet to get a funnel helps to pour.

[lastlight]

i wish hanna would sell a little canister with spoon similar to what elos does.

[Magickiwi]

Originally Posted by lastlight

i wish hanna would sell a little canister with spoon similar to what elos does.

I wish they'd just increase the automatic off time to five or ten minutes. I also wish they'd use a method that isn't so finicky to tiny variables and would be more consistent.

Having said that the phosphorous ULR checker does seem to be pretty reliable for me. It uses the same process as the phosphate but measures phosphorous; then you do some simple math to estimate your phosphate concentrations.