Hannah checkers - how much do you trust/like them?

[rosshamsandwich]

Nice to hear about the reliability of the Alkalinity checker. Perhaps I'll check it out.
Getting back to the Hanna Phosphate checkers: It seems there are two camps here; one group of people that are very happy with the "consistent" results and another group that is unhappy with the "inconsistent" results. Are the "unhappy" people doing something wrong during their testing-as Hanna would have you believe.
It is my firm belief that both camps are correct in their testing results/observations. What it really comes down to is it's a problem with quality control.
You either got a fully functioning unit or a lemon (which I got twice).
There are always "lemons" associated with any product. The lemons for the Phosphate/Phosphorous checkers are probably higher than they should be.
Along those lines, I decided to have my water sampled by Triton to see what my Phosphate levels were.
It seems that using Red Sea, Salifert and Hanna Checker for testing PO4 results all led to some inconsistencies:
The Checker would give the most inconsistent results. On the day I submitted the results to Triton, I used the Checker, 3 times and got results of Zero (first time ever) 0.12 and 0.25. (In the years I've been using the Checker, I receive a result of 0.10 ppm or above about 75%. I know this is not accurate.
The Salifert kit is somewhat difficult to read but it seemed to give results ranging between .05 - .10 ppm. Somewhat more consistent but not what I would consider reliable.
The Red Sea Kit would ALWAYS show a PO4 level of 0.04 PPM. While this is consistent, the fact that it always indicates this number causes me to question the reliability of the results.

Anyway, I received the results from Triton, two weeks ago, and the results indicated a PO4 level of 0.013 PPM. (Compared to 0.oo8 PPM when I tested with them about 2 and a half years ago).
So this indicates to me that none of the test kits or checkers are very accurate, ASSUMING,of course that the Triton method for testing IS more accurate.
Along those lines I will stop wasting my money on reagents and test kits and consider sending my water in for periodic testing, and not just for Phosphate.

I can't argue with Triton's results either. Sounds like Triton works best for you. If it ain't broke, don't fix it! Happy Reefing.

 

[mcarroll]

@David S What did you read to make you think the results from the different tests are directly comparable?

These testers are hard to use compared to traditional drip tests, so the problems folks have getting used to them are not surprising. Some of the things that matter to consistent results don't even occur to you if you're used to drip tests. Mostly, but not only, related to the handling of the glass vials.

 

[XNavyDiver]

Any scuttlebutt if/when Hanna will release a NO3 checker for saltwater? or are we closer to getting a unified field theory... anyone?

 

[Randy Holmes-Farley]

Anyway, I received the results from Triton, two weeks ago, and the results indicated a PO4 level of 0.013 PPM. (Compared to 0.oo8 PPM when I tested with them about 2 and a half years ago).
So this indicates to me that none of the test kits or checkers are very accurate, ASSUMING,of course that the Triton method for testing IS more accurate.

I don't know which may be more accurate, but I will point out that Triton and these test kits test for somewhat different things. So there shouldn't necessarily be a presumption that they will exactly match.

Triton and other ICP tests for phosphorus will detect any fully dissolved form of phosphorus, including organic forms (such as DNA and phospholipids). Triton claims that particulates (including whole bacteria) are removed, but there's a continuum between dissolved material and particulates and I'm not sure where the Triton method cuts off, or how effective bacteria and other particulate removal actually is.

Phosphate kits will generally not detect organic forms or any particulates that remain as particulates, but will potentially dissolve some inorganic particulates in the early stages of the test where the solution is rather acidic. They also do not detect certain polyphosphates.

FWIW, I'm not claiming these differences account for the result differences you observed, but I'm just challenging the validity of the comparison itself.

 

[mcarroll]

Any scuttlebutt if/when Hanna will release a NO3 checker for saltwater? or are we closer to getting a unified field theory... anyone?

Even if I still did "all the steps" for (e.g.) the Salifert NO3 test and then merely dumped it into a photometer to read, I'd be happy.

I'm not much better at reading all the shades of red than I am on the PO4 kit and shades of light blue. :mad:

 

[David S]

@David S What did you read to make you think the results from the different tests are directly comparable?

These testers are hard to use compared to traditional drip tests, so the problems folks have getting used to them are not surprising. Some of the things that matter to consistent results don't even occur to you if you're used to drip tests. Mostly, but not only, related to the handling of the glass vials.

Not sure I understand what you're asking.
I simply want a test kit (Phosphate or otherwise) or checker that provides reasonable accuracy and consistent results, otherwise why waste money on the products.
As far as the PO4 Checker, I can run 10 tests of the same sample water and wind up with 10 different results, most of which would probably test as being significantly different, from a statistical point of view. So my checker is neither consistent or accurate.
The Salifert and Red Sea PO4 kits give me consistent results (.05 - .10 for the Salifert and .04 for the Red Sea) . So they are consistent, but are they accurate?
I can tell you that while I don't test for PO4 that often, I've always gotten a .04 reading for the last couple of years - regardless of reagent - which was changed over time, from the Red Sea test. To me that raises some Red (pardon the pun) flags.
Ultimately, since I want to find out more about the chemistry of my tank, beyond the PO4 level, I'll be quite content to use the API or Triton service 2 - 4 times a year.