Which Hanna Phosphate Checker?

[nkaihani 42]

I don't find my Red Sea Phosphate kit to be very accurate... Going to buy a Hanna checker but which one?

736?

774?

And if anyone has one for sale I'm all ears  

[sharambil 13]

I heard ULR is good for long term use. Not sure how that correlates with the numbers.

[obrien.david.j 589]

I use Nitrate Low Range Colorimeter HI781.  No view which is best.

Edited April 6 by obrien.david.j

[dunpeal 77]

Same as Dave said. Want mine? I never use it

[nkaihani 42]

@dunpeal rocks! Got a phosphate and alk checker + some frags, thanks! 

[markv 4]

You want  HI774 Ultra Low Range Phosphate PPM Checker.

[SuncrestReef 3,616]

If you're serious about your PO4 readings, then you should decide between the original Hanna HI736 ULR Phosphorus, or the newer Hanna HI774 ULR Phosphate.  There are some slight differences between these two models.  The HI736 measures Phosphorus, and you need to use a conversion chart to figure out what the actual Phosphate reading is.  But the original HI736 is more precise and has a more narrow range than the HI774 which directly reports the Phosphate reading without any conversion, while the HI774 has a higher range and is slightly less accurate.

 

[SuncrestReef 3,616]

38 minutes ago, MasterChief said:

The 774 is the same as the 736. The 774 does the conversion for you and displays in PPM.  The accuracies of both meters are the same +-5ppb vs 0.02ppm (considering meter resolution...)

the light sources are the same

testing methods are the same

hell even the reagent works in both

 

They are not the same.  The resolution of the 736 is nearly 3x better than the 774:

HI736 = 0.0036066 ppm Phosphate
HI774 = 0.0100000 ppm Phosphate

[Oregonic 348]

I love my hannah PPM checker, I believe it is the ULR checker. I dont want to have to convert numbers. Hannah is also the easiest for testing PO4 in my opinion. 

[SuncrestReef 3,616]

52 minutes ago, MasterChief said:

This 👆🏻👆🏻  The 774 and 736 are pretty much the same, the 774 does the conversion for you. 

So you're simply going to ignore the fact that the resolution is nearly 3 times different as I posted above?

2 hours ago, SuncrestReef said:

They are not the same.  The resolution of the 736 is nearly 3x better than the 774:

HI736 = 0.0036066 ppm Phosphate
HI774 = 0.0100000 ppm Phosphate

 

[pdxmonkeyboy 2,694]

Milwaukie phosphotometer is more accurate but many times the cost. You can always print out the conversion table for the more accurate meter to convert it.  

The only thing the hi774 can do is measure the phos levels way outside the range you would want for a coral tank.