Neptune Aquatics

Hana Phosphate Meter- opinions?

Qwiv said:
Did you try the new meter? with the new Reactants? I complained and got sent new product.

The first model/reactants didn't work well. People doubled the time shaking the thing and got better results as the reactants were not devolving.
I think they are now working on liquid reactants, which I would prefer. So far, I don't think the issue is the meter, but the reactants which they can improve over time. I got consistent numbers reading the control sample.
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Not sure if it is new model or not, how can I tell?

For me the regents dissolve OK but it take some time to shake, there is absolutely no way to dissolve regents in the given time window (30 second?), I always use the two tubes and start the test after I have two tubes ready, one with water sample & other with dissolved regents.

I will prob. bug hanner to get some new regents to check out, what should I say? The regents are hard to dissolve?

seminolecpa said:
Talking out of my butt here, but I believe you can have a low reading and still have phosphates. They are just being used by stuff in your tank.
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Definitely!

I take N & P reading as indicator of balance of nutrient import and export, as Rich mentioned what important is trend, not specific numbers.

I mainly test N as gauge of nutrient & don't test P often, the recent test I wanted to see what is impact from carbon dosing, I kind of expect lower reading since the carbon dosing bring my N from 5 - 10 to less than 1.

GreshamH said:
Pretty sure cyanbacteria doesn't need all (any?) that much PO4, unlike microalgeas & macroaglaes
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From what I read cyanbacteria is combo of bacteria & algae, they feed on multiple sources, they take P but not as dependent on it like algae.

So what would be other options to beat it other than manual remove? My cyano problem mainly on sand bed since I have sugar grain can not blow with too much flow.
 
Thales said:
JAR said:
Thales said:
I found I couldn't get repeatable results on the same water sample. Sometimes the range was extreme.
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Was was your control? :D
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Funny! Though it wasn't needed to see if the device yielded consistent results, I ran the water sample through our lab at work because initially I wanted to see the accuracy of the thing, consistency was an after thought. :D

I am waiting on new reagents that are supposed to be in the mail.
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I was thinking that you would come back with something like...
"I used 10 different testers all on the same water at the same temperature.
The batteries in each of the 10 units were verified good. We also tested distilled water. Then I had my buddy (the brain surgeon) do the same thing in case I was the issue.
We again ran all the same tests with 10 different reagent bottles.
This was all done in a clean room with controlled lighting.
All of these tests resulted in inconsistent results."
 
JAR said:
Thales said:
JAR said:
Thales said:
I found I couldn't get repeatable results on the same water sample. Sometimes the range was extreme.
Click to expand...
Was was your control? :D
Click to expand...

Funny! Though it wasn't needed to see if the device yielded consistent results, I ran the water sample through our lab at work because initially I wanted to see the accuracy of the thing, consistency was an after thought. :D

I am waiting on new reagents that are supposed to be in the mail.
Click to expand...

I was thinking that you would come back with something like...
"I used 10 different testers all on the same water at the same temperature.
The batteries in each of the 10 units were verified good. We also tested distilled water. Then I had my buddy (the brain surgeon) do the same thing in case I was the issue.
We again ran all the same tests with 10 different reagent bottles.
This was all done in a clean room with controlled lighting.
All of these tests resulted in inconsistent results."
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Well, duh. That part was obvious.
 
OK!
I got one of these gizmos for Christmas.
I guess I was not so naughty this year.

I was able to get consistent readings on the two samples that I tested.
I ran the same two samples 6 times each through the meter ant the difference was +- 2ppb

Multiply your reading by 3.066 to convert P to PO4. The HI 736 measures in ppb, so if you want ppm divide by 1000.
http://reefcentral.com/forums/showthread.php?t=1848082

Example:
12 x 3.066 = 36.792 / 1000 = .0367 ppm PO4

My readings were as follows

Sample 1
24
24
23
24
23
25

Sample 2
27
25
25
25
26
25

average test result ppb P = 24.66666666666666666 x 3.066 = 75.628/1000= 0.075628 ppm P04

Time to run some GFO and see what happens!
 
Shoot, I bought the phosphate HI 713 checker last night. I did not get the ULR phosphorus checker HI 736. I read the thread on reef central saying the ULR is more accurate. Oh well. I tested three times last night and got .07 ppm .00 ppm and .06ppm. So I guess its around .07 +/- 5%

With such a large error range is this worth testing? There is no way of not having a measurable amount of PO4 so this is only going to give a general range of the level.

This is for the ULR phosphours checker, its more accurate but still has a large range of error.

The HI 736 gives you a small but distinct advantage in low range phosphate testing.

For example, if you tested with the HI 736 and your results were 10 ppb phosphorus:
10 ppb phosphorus = ~30.7 ppb phosphate

Since the error range of the HI 736 is +/- 10 ppb +/- 5% of the reading, the possible range of actual reading is:
1 ppb phosphate to ~62.9 ppb phosphate (1-20.5 ppb phosphorus)

This is the same as:
0.001 ppm phosphate to 0.063 ppm phosphate

This means the effective error range has been decreased from +/- 0.04 ppm (the HI 713) to +/- 0.03 ppm

More importantly, the lowest positive detection limit of the HI 736 is 1 ppb (or 0.001 ppm) phosphorus, much lower than the HI 713 (which is 0.04 ppm). This means if the HI 736 reads 4 ppb, regardless of the size of the error range, phosphorus is definitely present in your water.
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I must say I am impressed with Hanna's tech support. I have an issue with my checker reporting bad battery, it works about 50% of the time, most often when it starts it reports Bad Bat even with a new battery installed, it even craps out in the middle of a test. I called Hanna and they said they would replace it with a new unit, I asked if it would be possible to get the HI736 ULR phosphorous kit and he said sure no problem, its the same cost and would be better. Very nice support. Though I would have been happy with a working meter this is a nice upgrade. Also the vials leak when shook and he said there are plastic caps that go on before the screw on caps, I did not see these in my kit.

I think my next purchase will be the Alk meter, with the new liquid regents its supposed to be very accurate and easy to use.
 
I have the ALK meter. The implied accuracy is well over what I was expecting. It makes calculating the dose of 2 part in a small tank better. Hoping CA is on the way soon. The liquid reactant is much easier to work with as well.

I tossed those plastic caps as they get stuck inside the glass for me. Of the 3 meters I have, only one of the 6 cuvettes leaks for me and I use it only for the calibration step only.
 
If anyone orders more reagents let me know. Mine expired last month still have the older one but my understanding is that it uses the same reagents.
 
seminolecpa said:
If anyone orders more reagents let me know. Mine expired last month still have the older one but my understanding is that it uses the same reagents.
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I will need some too.
I have 3 packets left.
I plan to use them in the next 3 weeks.
 
I picked up one of the Phosphorus meters recently.

I was surprised at the condition of the cuvettes. Both had horizontal scratches on them ~1/3 of the way down from the top. Deep enough to catch a fingernail. Also had other random scuffs and flaws on the glass.

That said, I was able to get repeatable results on multiple tests.

Anybody else get scuffed and/or scratched cuvettes?
 
Hmm IIRC they actually came out with new cuvettes Norm. I wonder if yours are the old ones. Then again I could be speaking out my Manus.
 
I was surprised because of two things.
My cuvettes had minor scratches but also...
There is a noticeable fingerprint on the inside of the LCD lens.
I'm still getting repeatable results on multiple tests.
That being said. I need more reagent.
I think I'm addicted to it.
Group buy anyone?
Rich, did you get your pile of new reagent yet?
 
GreshamH said:
Hmm IIRC they actually came out with new cuvettes Norm. I wonder if yours are the old ones. Then again I could be speaking out my Manus.
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Funny video :D

Looked on the Hanna websites and didn't see anything about new cuvettes. What's different with the new ones?
 
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