Got my water test results back from ATI

jbird0420 · 12/14/2018, 07:16 AM

Hi all,

I sent a sample of my tank water and RODI water to ATI for further testing. ATI said my Salinity is 30.31 PSU they suggest 35.00 PSU. I use a Milwaukee Digital Seawater Refractometer and the sample I sent to ATI read 1.026 the day I sent it out and I try to make a conscious effort to check my salinity daily.

I calibrate the refractometer each and every time with RODI water and it normally reads 1.025-1.026. So my question is my Salinity really way off from what ATI recommends?

Thanks!

mcgyvr · 12/14/2018, 09:00 AM

Time for a 3rd (or more) opinion..

jbird0420 · 12/14/2018, 10:12 AM

Agreed!

Quote:

Originally Posted by mcgyvr

Time for a 3rd (or more) opinion..

saf1 · 12/14/2018, 12:01 PM

Quote:

Originally Posted by jbird0420

Hi all,

I sent a sample of my tank water and RODI water to ATI for further testing. ATI said my Salinity is 30.31 PSU they suggest 35.00 PSU. I use a Milwaukee Digital Seawater Refractometer and the sample I sent to ATI read 1.026 the day I sent it out and I try to make a conscious effort to check my salinity daily.

I calibrate the refractometer each and every time with RODI water and it normally reads 1.025-1.026. So my question is my Salinity really way off from what ATI recommends?

Thanks!

Interesting. I had similar results with ATI a couple months back along with high tin and zinc. I use the green Milwaukee digital and while old has never been dropped. I also calibrate before every use.

I've since ordered the plastic non digital more for curiosity sake and emergency backup than anything else although it is reading the same. Not sure what ATI is doing or if my salinity was actually that low at the time of testing - it could have been although I don't believe so.

In any case I'd test with another device at home before doing any changes.

mcgyvr · 12/14/2018, 07:59 PM

Using some 35ppt cal fluid to ensure you are reading 35ppt with your meter would be enough for me to send a question back to ati about it and ask what's up..

bertoni · 12/14/2018, 09:51 PM

I agree with getting a 35 ppt calibration fluid. The PinPoint 53 ms solution is fine for refractometers and hydrometers, as well as conductivity meters.

RobZilla04 · 12/20/2018, 08:14 AM

Is the temperature difference the culprit for the resulting salinity results?

Food for thought.

bertoni · 12/20/2018, 10:00 PM

Hopefully not. Refractometers should be relatively immune to the sample temperature, and most meters are compensated. I don't know how the testing companies are measuring SG, though. I'd check the documentation on any meter before making any assumptions.

12/14/2018, 07:16 AM	#1
jbird0420 Registered Member Join Date: Jun 2008 Location: Parrish, Florida Posts: 1,079	Got my water test results back from ATI Hi all, I sent a sample of my tank water and RODI water to ATI for further testing. ATI said my Salinity is 30.31 PSU they suggest 35.00 PSU. I use a Milwaukee Digital Seawater Refractometer and the sample I sent to ATI read 1.026 the day I sent it out and I try to make a conscious effort to check my salinity daily. I calibrate the refractometer each and every time with RODI water and it normally reads 1.025-1.026. So my question is my Salinity really way off from what ATI recommends? Thanks!

12/14/2018, 09:00 AM	#2
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	Time for a 3rd (or more) opinion.. __________________ Who me?

12/14/2018, 07:59 PM	#5
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	Using some 35ppt cal fluid to ensure you are reading 35ppt with your meter would be enough for me to send a question back to ati about it and ask what's up.. __________________ Who me?

12/14/2018, 09:51 PM	#6
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	I agree with getting a 35 ppt calibration fluid. The PinPoint 53 ms solution is fine for refractometers and hydrometers, as well as conductivity meters. __________________ Jonathan Bertoni

12/20/2018, 08:14 AM	#7
RobZilla04 Registered Member Join Date: Sep 2016 Location: St. Augustine, FL Posts: 1,857	Is the temperature difference the culprit for the resulting salinity results? Food for thought. __________________ 90g Mixed Reef

12/20/2018, 10:00 PM	#8
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	Hopefully not. Refractometers should be relatively immune to the sample temperature, and most meters are compensated. I don't know how the testing companies are measuring SG, though. I'd check the documentation on any meter before making any assumptions. __________________ Jonathan Bertoni