Testing Salinity - What do you use?

Crashjack

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I use a freshly calibrated refractometer every now and then and use a swing arm to verify my make-up w/c water matches my DT water. However, I would love something electronic that was simpler but just as accurate as a freshly calibrated refractometer. I'm physically handicapped and the calibration plus the process I go through to guarantee consistency, make me dread periodic refractometer testing.
 

Paul B

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Long Island NY
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I am not sure why so many people are focused on salinity. It isn't that important and fish and corals can and do live in a wide range of salinity.
 

Potoooooooo

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I am not sure why so many people are focused on salinity. It isn't that important and fish and corals can and do live in a wide range of salinity.
I only test it when I'm making water for a water change. My controller has a probe for it, I don't control anything with the reading. The readings are usually what I expect., when they are wrong, it's a probe error (air bubble, detritus, etc.) and not an actual change in salinity.
 

phatduckk

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I use a Milwaukee MA887, only time it has off readings is if there's a bubble in the sample well or a lot of ambient light. I dropped it and cracked the display but it still works!
plus you can calibrate it with RO which is nice. When doing anything major to the DT I just take a few drops from the ATO, calibrate it and run a test
 

phatduckk

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I have a Milwaukee also but I am thinking of picking up a Hanna also just to verify results.
I do it backwards... my Milwaukee verifies my apex. but while mixing salt its just the Milwaukee. I do a max water change of 10-20% so if its off a little it doesn't really matter
 
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piranhaman00

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Glad to find this forum!

I always used a cheap refractometer, have to calibrate every single use.
I recently purchased a VeeGee, actually holds calibration, but really want to try a conductivity probe, looking at the pinpoint.

I have been doing loads of research on this seemingly simple question, which is the best? The milwaukee precision is too high for me (+/- 2ppt) and I hear they all read high.

The hanna looks interesting to try!
 

Dr.Reef

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Honestly either I am lucky or I got a real good unit or I did something right.
I have several refractometers from cheap ones to more expensive ones. Also have apex conductivity probe plus I have the Milwaukee salinity unit as well.
DD h2o refractometer I use. I calibrated it with a standard 35ppt solution and it has NEVER lost its calibration. I myself doubt it sometimes and recalibrate but it comes back 100% perfect everytime.
It's been holding calibration for minimum 3 yrs as far I remember.
Milwaukee unit even though calibrated with same standard is always 0.002 units off. But still consistent and never loses its calibration either.
 

Kups

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The Vee Gee seems to be working. It's definitely consistent, it just doesn't match my calibration fluid. The calibration fluid could be off though.
 
I use a veegee. It's nice. My Milwaukee green brick was off by like 3pt. Even calibrated fluid was showing way off
 

piranhaman00

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The Vee Gee seems to be working. It's definitely consistent, it just doesn't match my calibration fluid. The calibration fluid could be off though.
That is because the VeeGee is calibrated at 20C. All calibration fluids I can find are calibrated for a refractive index at 25C. RI changes with temp so at 20C the fluid will be off. However, I have found this difference to be very minimal but might be different across fluid manufacturers.

The VeeGee must be calibrated with RODI water. RODI has RI of 1.000 at 20C. The VeeGee is then calibrated across the entire range of readings (unlike cheaper refract).

I have been liking my VeeGee but bought a Hanna over the sale weekend to try out. I want to have a backup. Hoping the Hanna can become the proffered.
 
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