Are these ICP numbers dangerous for fish?

[mac1284]

Hello, I have a 90 gal water box tank I cycled with doctor Tim’s about 3 months ago.

I just did a ATI ICP test and got back some interesting numbers.
It says my salinity is 32.66, I tested it with my refractometer and so did my LFS and came back with 35% 1.026. My tank has nothing in it no corals or fish just substrate and rocks. I mix my own salt water which is water box’s reef salt. My RODI analysis came back perfect zero on everything.

Any insight or help would be greatly appreciated.

https://lab.atiaquaristik.com/share/ad5aea372f525d24033d

 

[Dan_P]

Hello, I have a 90 gal water box tank I cycled with doctor Tim’s about 3 months ago.

I just did a ATI ICP test and got back some interesting numbers.
It says my salinity is 32.66, I tested it with my refractometer and so did my LFS and came back with 35% 1.026. My tank has nothing in it no corals or fish just substrate and rocks. I mix my own salt water which is water box’s reef salt. My RODI analysis came back perfect zero on everything.

Any insight or help would be greatly appreciated.

https://lab.atiaquaristik.com/share/ad5aea372f525d24033d

Is your refractometer calibrated? If so, trust your measurement. If not buy a reference standard. You will need it.

 

[mac1284]

Is your refractometer calibrated? If so, trust your measurement. If not buy a reference standard. You will need it.

As best to my abilities it is. I ATC refractometer and I use aquatic experts calibration solution.

 

[Dan_P]

As best to my abilities it is. I ATC refractometer and I use aquatic experts calibration solution.

Sounds like your refractometer results can be trusted.

 

[TangerineSpeedo]

I have a refractometer (2) which I do not use. Hanna salinity tester, Milwaukee electronic refractometer, and a Tropic Marin hydrometer. A lot of things can affect the ways we read salinity. You would think it would be simple, but no. Things like temperature, organics, etc. can vary the readings of different devices. It is important that you understand how each of your testing devices work and what environmental influences affect them.
I would recommend a TM hydrometer as a reference, so you know. But even that has to be set up at 25 deg Cel or 77F to be accurate. So that opens up another can of worms... Is my temperature measuring device accurate?
So in the end, you want to get close to optimum and just be consistent about it.

 

[gbroadbridge]

As best to my abilities it is. I ATC refractometer and I use aquatic experts calibration solution.

I would make a DIY calibration solution and check your refractometer against that and use that for future adjustments.

Bottled calibration solutions can be incorrect for many reasons, but if you make your own you can be confident that the salinity is always correct.

https://reefkeeping.com/issues/2004-06/rhf/index.php

 

[crabgrass]

To answer OPs direct question, regardless of ICP or your own measurement, you are in a safe range for fish. It’s likely the fish at a LFS or online are in tanks with the same or less salinity than either of the measurements above

It would be good to identify or cross check ICP vs your own. It is possible that it was a testing/timing issue as well.

 

[taricha]

Randy's recently posted salinity calibration article...
https://www.reef2reef.com/threads/reef-aquarium-salinity-diy-calibration-standards.1042851/

 

[Randy Holmes-Farley Verified Community Expert]

I agree that there's no evidence that 32.6 ppt (or 35 ppt) is a problem for fish.