New Phosphate ULR vs Phosphorus ULR

[jurgenph]

What good is some extra accuracy when a quarter of tests are rushed and failed due to 2 min time limitation on the Phosphorus one?

it's a 3 minute timeout shut off, not two.
it shuts off two minutes AFTER the test.

Auto-off	after three minutes of non-use and two minutes after reading

so you have three minutes to:

take out the vial
add the reagent powder
shake 2 minutes.
return the vial to the checker and press the button.

i start a 3 minute timer after doing the C1 calibration, never ran out of time or felt rushed.
cut open the reagent powder before starting, have it ready to go.

ps: for those doing the conversion, you can just print their conversion table, and keep it in the checker box. that's what i do

https://hannainst.com/resources/aquarium/guides/phosphorus-to-phosphate-conversion-table--hanna-instruments.pdf

J.

 

[foxt]

shake 2 minutes.

This may not be what everyone else should so, but I only vigorously shake for 1 minute. I did a bunch of comparisons between the 2 mins and the 1 min, and didn't find much difference. I too set a timer: one at 1 min to tell me when to stop shaking, and one at 3 mins after I have pressed the button to remind me to go look at the result because I would forget about it, or miss the short window during which the result is displayed.

 

[homer1475]

Your not supposed to violently shake the vial, that causes micro bubbles and may not read properly. Your only supposed to slowly turn the vial up and down to mix the reagent. If you do the mixing properly, there is a huge difference in how much of the reagent is mixed at the 1 and 2 minute mark.

 

[foxt]

LOL...ok same question. Curious why you use the 774 first instead of the "more accurate" 736. Is the procedure easier? Quicker test? I haven't bought mine yet, and generally I'd go more accurate but like to know if there's something else to consider with real world experience.

The sad truth is that I dropped my 736 in the sump one day, and thought it was dead. I tried drying it out, cleaning the inside as best I could, etc. But it would just be stuck in some sort of diagnostic mode. So, while at RAP, I asked the Hanna people about it, and they suggested there was no saving it, and sold me a 774 (they didn't have the 736 with them).

Magically, one day I discovered that the 736 had been reborn, and it was working again. I kept using both of them for a while, just to see how they compared. Plus I had the 736 reagents, so I figured I would use them up. I was really surprised that the 736 was performing well, since it had seemingly died, but go figure. After a while, I decided that I would just use the 774 since I didn't need to do the math for the conversion, and since the numbers between the two seemed to line up consistently within the margin of error. Plus the 774 stays on longer than the 736.

Every once in a while, for whatever reason, I get an unusually high result on the 774, not crazy high, but higher than "normal". When that happens, I turn to the 736 and do two tests, and the 736 usually confirms the 774 reading (or close enough to it), and I go looking for a cause for the increase.

 

[foxt]

Your not supposed to violently shake the vial, that causes micro bubbles and may not read properly. Your only supposed to slowly turn the vial up and down to mix the reagent. If you do the mixing properly, there is a huge difference in how much of the reagent is mixed at the 1 and 2 minute mark.

Could be. I wouldn't say I "violently" shake it, but I do shake it more than slowly moving it up and down. I've also noticed that whatever bubbles may have been in the vial at the start are gone when I remove the vial after the test is complete. I never see any undissolved reagent in the vial, and as I said, not suggesting that others try this, but I did enough comparison tests to satisfy myself that whatever I am doing doesn't give different results whether I do it for 1 minute or two.

I'll go try it again later today and see what I get ...

 

[homer1475]

Actually just watched a video from @Hanna Instruments on proper use of the ULR. I had allways thought you just inverted the vial, and back up in a rather slow motion to mix the reagent. In the video they actually shake the vial. I guess I'll start shaking it.

 

[Quietman]

Did that to my Pinpoint pH meter on literally day 2 after getting cycle started. No amount of DI saved that bad boy. Next purchase was waterproof pH pen well, not exactly 'next'. Next right after I got over being disgusted with my fumble fingered self and got tired of using reagent pH tests. Oh, if you ever talk to my wife - she thinks it just stopped working so be a pal and don't mention my incompetence, she laughs at me enough.

The reagent refills are the same price, improved accuracy (although I doubt enough that it results in any change in how I do things). Seems like everything else is a push and I can use the 2 min timer to make sure my cat like reflexes stay sharp - or more likely it'll be the first sign of 'getting to be that age' when I can't manage to complete it in time any longer.

Thanks for the feedback!

 

[foxt]

Actually just watched a video from @Hanna Instruments on proper use of the ULR. I had allways thought you just inverted the vial, and back up in a rather slow motion to mix the reagent. In the video they actually shake the vial. I guess I'll start shaking it.

It's the alk checker that you just invert like that, 5 times. That one only takes me about 5 seconds so I don't try to save time and cut it short