High salinity! How slow to lower it?

[Floyd-]

Ok here are the results...
Using RODI water and salt and digital scale I made the solution.
Hanna read 1.025
Refractometer read 1.027
Swing style. 1.028

Testing the tank water I got:
Hanna- 1.024
Refrac-1.028
Swing-1.028

Im at a loss. Just pick one and hope its right and consistent?

 

[Jon's Reef]

Ok here are the results...
Using RODI water and salt and digital scale I made the solution.
Hanna read 1.025
Refractometer read 1.027
Swing style. 1.028

Testing the tank water I got:
Hanna- 1.024
Refrac-1.028
Swing-1.028

Im at a loss. Just pick one and hope its right and consistent?

Did you make the correct solutions for each measurement per the link?

 

[Floyd-]

Did you make the correct solutions for each measurement per the link?

Apparently not... I only made a single solution for testing all 3.
Can someone give me a cliff notes version of what I need to measure out for all 3? That website is very long winded and explains everything in insane detail. I just need to know how much salt and water for each tester.

 

[Randy Holmes-Farley]

Ok here are the results...
Using RODI water and salt and digital scale I made the solution.
Hanna read 1.025
Refractometer read 1.027
Swing style. 1.028

Testing the tank water I got:
Hanna- 1.024
Refrac-1.028
Swing-1.028

Im at a loss. Just pick one and hope its right and consistent?

Which solution did you make? Those devices will not read a single sodium chloride standard to be the same. They need different standards.

 

[Randy Holmes-Farley]

Apparently not... I only made a single solution for testing all 3.
Can someone give me a cliff notes version of what I need to measure out for all 3? That website is very long winded and explains everything in insane detail. I just need to know how much salt and water for each tester.

Here’s my article with all three different recipes for different devices:

Reef Aquarium Salinity: Homemade Calibration Standards by Randy Holmes-Farley - Reefkeeping.com

 

[Floyd-]

Which solution did you make? Those devices will not read a single sodium chloride standard to be the same. They need different standards.

I did 79.9g of salt and 2104g of RODI water.

Its real hard to find what I need in that page. It dang near covers the origin of salt and water its self. Its like trying to get a recipe online. First they talk about how its a family recipe and its been handed down 10 times and the tomatoes come from George down the street on the left and you just need to have a list of ingredients and thats it.

Guess ill snuggle up and try and figure it out when I have more time.

 

[Dburr1014]

swing arms aree trash why would you trust it over hanna

If it's calibrated, why is it trash?

 

[Garf]

I did 79.9g of salt and 2104g of RODI water.

Its real hard to find what I need in that page. It dang near covers the origin of salt and water its self. Its like trying to get a recipe online. First they talk about how its a family recipe and its been handed down 10 times and the tomatoes come from George down the street on the left and you just need to have a list of ingredients and thats it.

Guess ill snuggle up and try and figure it out when I have more time.

Presumably you’ve made the refractometer solution correctly to 35ppt. So, get your tank to 35ppt with it. Then calibrate the Hanna with your tank water, if you want a back up, or eBay it. You can put your swing arm in a time capsule and stick it in the garden, it’ll confuse the hell out of folks in the future. My refractometer is all I need.

 

[Randy Holmes-Farley]

I did 79.9g of salt and 2104g of RODI water.

Its real hard to find what I need in that page. It dang near covers the origin of salt and water its self. Its like trying to get a recipe online. First they talk about how its a family recipe and its been handed down 10 times and the tomatoes come from George down the street on the left and you just need to have a list of ingredients and thats it.

Guess ill snuggle up and try and figure it out when I have more time.

Read the article that I posted as it makes it super clear what to make for what device.

The standard you made is for a refractometer.

 

[Reefbuds]

I've had a swing arm for 10+ years. The same one in fact, accurate as the day I got it. Never had issues with salinity with it.. I'm dreading the day I have to get a new one

 

[Garf]

I've had a swing arm for 10+ years. The same one in fact, accurate as the day I got it. Never had issues with salinity with it.. I'm dreading the day I have to get a new one

I probably didn’t clean mine properly, I certainly didn’t calibrate it, and the bubbles on the arm, jees. It was a long time ago though, I’m probably biased against them, admittedly.

 

[Dburr1014]

Mine is 8 years old. I recently had questioned it and my refractometer. My sg went to 1.030,corals weren't opening. Found a standard in my aquaforest test kit and straightened out my refractometer. Then I fixed my tank salt and checked that against my swingarm. Turns out my swingarm was right on the money.

 

[Randy Holmes-Farley]

Swing arms do a surprisingly good job of temperature correction, but they are hit or miss on accuracy (IME):

Chemistry and the Aquarium: Specific Gravity: Oh How Complicated!

This month, Randy explains and reviews specific gravity.

reefs.com

from it:

So how do these hydrometers measure up? In my tank the water was measured to be S=35 ± 0.5 by conductivity. Using the Deep Six swing arm hydrometer I got readings of S=32.5 ± 0.5 at 81 °F and S=32 ± 0.5 at 68 °F. Using the SeaTest I got S=34.5 ± 0.5 at 81 °F and S=34 ± 0.5 at 68 °F.

For the standard type Tropic Marin hydrometer, I got a 77 °F/77 °F specific gravity of about 1.0265 ± 0.0003 (Figure 4), which compares well to the expected value of 1.0264.

 

[Floyd-]

From what im seeing at the moment the swing arm is staying really stable. I really dont like the refractometer for the extra stuff involved and I like the Hanna for the speed and convenience but im doubting the accuracy.

 

[scottj6]

I seriously recommend the Milwaukee Salinity digital refractometer. The most accurate I've used as long as your being mindful of the temperature and zero the device at least twice a week with RODI.

+1 I love my Milwaukee. Its the most accurate I have found

 

[mrpontiac80]

I know this is an older thread but my Hannah checker has been my tester. Compared to my friends Milwaukee it seems my Hannah reads 1.025 and my tank water on his Milwaukee reads 1.028.

I decided to buy a tropic Marin hydrometer and test it feeling like the hydrometer would be accurate. So far it seems the Hannah reads lower than it actually is. With temperature it shows actual salinity to be 1.0279

 

[Randy Holmes-Farley]

I know this is an older thread but my Hannah checker has been my tester. Compared to my friends Milwaukee it seems my Hannah reads 1.025 and my tank water on his Milwaukee reads 1.028.

I decided to buy a tropic Marin hydrometer and test it feeling like the hydrometer would be accurate. So far it seems the Hannah reads lower than it actually is. With temperature it shows actual salinity to be 1.0279

How did you calibrate these devices?

Did you ever check the hydrometer in a standard?

 

[mrpontiac80]

How did you calibrate these devices?

Did you ever check the hydrometer in a standard?

I’ll be honest, I don’t want to spread false info so if my post needs to be deleted or edited, please let me know.
To answer the question I was doing this as I posted, came across this thread while waiting on temps and posted the above. The hydrometer was not calibrated by myself. I don’t even know if I can. The Hannah was calibrated with the Hannah calibration packet intended for the checker.
The salt water was from my mixing bin that was 1.025 as per my Hannah.
I used 3 food temperature probes and my Hannah…. I feel the Hannah is as calibrated as anything as far as accurate especially after taking all the temps with different probes.
The hydrometer says to be accurate at 77 degrees so I waited till all the probes including Hannah showed 77 and took a final reading of the TM hydrometer showing 1.0264 while my Hannah shows 1.025.
I wonder how much closer if any it would be switching to ppt. But I used my last Hannah calibration packet and will test again later.