Let's talk about the hanna meters....

[jcom]

I'm going to give the "lights out" test a go tonight and see if I get an increased reading.

 

[ReeferRob]

Just did two test as my lights haven't gone on yet for the day. Made the line, used one vial, micro fiber clothe basically everything listed here in this thread. Test on was .12 which is way down from last weeks test of .38 which is good. But the second test was .22, so Im back on the fence with these things......

 

[Troylee]

Well I they can make a syringe that is perfect why can't they a covent that's perfect.... Sounds like a big quality issue with the vials here....arrrrrrr... Now I'm getting frustrated knowing I put my time and money into these things to only find out I have been using it wrong.... Biggest problem is that's not my fault, it should state these things in the directions or charge 5$ more to make a covent with the nesacary marks for a true reading....:(

 

[Troylee]

Btw do all these issues arise with it's big brother??? The old school, expensive ones???

 

[ronnie]

FWIW, highly accurate cuvets are very expensive. They machine the glass optically - this is a very tedious process.

There is a high degree of user error involved in these tests - any spillage of the reagent, improper mixing, smudge on the cuvet, etc. can cause errors.

I think it is a good general test, but definitely not something I'd bank on for pure accuracy.

 

[ReeferRob]

I agree TL, I think its bull donky. Too many corners were cut to make this thing $40 bucks. I would have spent the extra .25 cents for them to add the extra text to the directions to inform us that they choose to use inferior glass vials and not make the notch.

 

[Paul_N]

Btw do all these issues arise with it's big brother??? The old school, expensive ones???

I have the old school one and really don't have issues with how I place the cuvet in. I have done numerous retests and got the same result or maybe off by like .01. For me I am looking for a range (.07 and under) so I don't mind a .01 or even .02 variation. Just my .02

 

[Paul_N]

FWIW, highly accurate cuvets are very expensive. They machine the glass optically - this is a very tedious process.

There is a high degree of user error involved in these tests - any spillage of the reagent, improper mixing, smudge on the cuvet, etc. can cause errors.

I think it is a good general test, but definitely not something I'd bank on for pure accuracy.

Ya I went to a site that sells them and they are $$$. They also sell a specific cuvet cleaner depending on the cuvet and what you test. that was pricey too if I remember correctly.

 

[jcom]

Reefer Rob, have you tested your Po4 with a Salifert kit? Just curious what it's saying in comparison to the Hanna.

It is obviously necessary to keep the cuvet clean and streak free. Even when you think you have it pretty clean, if you look through it and twist it in good lighting, you're still likely to see streaking. Those little cloths that come with nicer sunglasses are ideal to use.

And I agree to other sentiments that if it's within 0.01 or so from the $300 model, what more could we really expect from the pocket meter?

 

[Troylee]

Reefer Rob, have you tested your Po4 with a Salifert kit? Just curious what it's saying in comparison to the Hanna.

It is obviously necessary to keep the cuvet clean and streak free. Even when you think you have it pretty clean, if you look through it and twist it in good lighting, you're still likely to see streaking. Those little cloths that come with nicer sunglasses are ideal to use.

And I agree to other sentiments that if it's within 0.01 or so from the $300 model, what more could we really expect from the pocket meter?

my whole thing here is the lack of information in the directions.... i under stand completely it is cheaper made than it's counter part "hence the price tag" but why do we have to make mistakes and be misled here to come to the truth about it.... i have been dosing the crap out of my tank with amino acids because i always get a zero reading.... if it was to crash who's fault is it??? ya im obviously not using it correctly, BUT!!!!!!! im using it according to the directions.... seriously put a mark on the covent or explain in the directions that you only use one vial and it must be marked to ensure a accurate test....as it stands were just playing with disaster and taking everything for granted imho, following there directions..... :(

 

[Mr Beardsley]

my whole thing here is the lack of information in the directions.... i under stand completely it is cheaper made than it's counter part "hence the price tag" but why do we have to make mistakes and be misled here to come to the truth about it.... i have been dosing the crap out of my tank with amino acids because i always get a zero reading.... if it was to crash who's fault is it??? ya im obviously not using it correctly, BUT!!!!!!! im using it according to the directions.... seriously put a mark on the covent or explain in the directions that you only use one vial and it must be marked to ensure a accurate test....as it stands were just playing with disaster and taking everything for granted imho, following there directions..... :(

I hear what you are saying, and I agree that the directions for use are awful. However, I am glad that I have both the device and have found information online to help me use it. :bigsmile:

 

[ksc]

The Hanna po4 meters have been proven to be very innacurate. Anything under .1 and you might as well pick a number out of a hat...

 

[ronnie]

The Hanna po4 meters have been proven to be very innacurate. Anything under .1 and you might as well pick a number out of a hat...

Compared head-to-head with the $300 version, it has fared very well - especially for the price range it is in. Where are you getting the inaccuracies of anything under .1?

 

[ksc]

It has? What lab tested it?

 

[ronnie]

You answer my questions first :D

 

[drainbamage]

great thread, and good to know all this info as though i don't have one, been seriously considering purchasing one.

One thing I might point out with only seeing pictures of 0 results is something I keep in the back of my mind all the time with this hobby- Most folks who put up pics are proud of the stuff they're pics show. You don't see too many pictures of something gone horribly wrong as well, people don't like to show it. When i gave myself a mini-crash in my tank, my picture posting went to 0 while I hid my shame, when certain things are looking decent, I feel more confident to put stuff up for display. As such I doubt you'll see people showing off "hey, look how high my phosphates show!" especially given the internets tendency to scold people like that, ya know?

 

[ksc]

Well, first of all most reefers are looking for readings below .04. According to Hanna themselves, the margin of error is .04, or 100%. You'll have to dig through the Chemistry Forum on RC to see the testing results.

 

[ronnie]

I've read the post on RC in the chemistry forum. No where did it state that it was worthless if phosphates were under .1 - and there was one gentleman that actually suggested that ANY phosphate meter was essentially worthless under 1ppm.

I'm not saying it is or isn't correct, but for what it is, I think it is a great tool - especially at $40.

 

[AndyDuckets]

i was thinkin about getting one of these meters...i mean its only 40 bucks... thank you for posting this thread; lots of usefull information and insight on how consistant one must be to get accurate readings!

 

[ksc]

Usually when somthing is a great tool, you know if it is or it isn't correct. That's the problem....