I have no idea what my salinity truly is. Please help.

[MuscleBobBuffPants]

When I first started this journey. I chose a Hannah salinity checker because I had heard so many great things about it. It was supposed to be accurate, hold a calibration and easy to use.
After a month (which is listed in the instructions) I recalibrated my checker, I checked my salinity before the calibration and got 34.8 or so. After the calibration I got a salinity Of 36.5!
So I immediately ordered a refractometer from brs to have a backup method of testing my salinity.

through a bunch of tests (calibrating multiple times along the way) I realized that my salinity checker was giving me incorrect readings even 4-5 days after calibration. After a long process of getting my checker replaced by Hannah. I got a new one, the first thing I did was calibrate it With one of the packets. I calibrated the device. And then took a measurement of the exact same calibration fluid. It gave me a reading of 33.8 instead of the 35.0 from calibration fluid it had Literally just used it to calibrate itself.

I’m at a loss. My refractometer suspiciously gives me a 35.0 reading a lot more often than I’d think. Like I’m not sure I’m that good at mixing seawater. I check my calibration with the refractometer every time before I use it to measure my tank water.
I even purposefully make higher and lower salinity ratios just to check and make sure my refractometer is not somehow stuck on 35ppt.

My biggest issue is that I’ll use my refractometer and get my salinity to 35ppt, then use both of the Hannah checkers( after I calibrated them) [did I mention this calibration fluid costs A dollar each time!!] and they both give me numbers that are 3-4 points off. Please help me. I’m not sure what I should do next. I’m constantly paranoid that I have no idea what my salinity truly is and it’s driving me insane.

 

[Katie M]

You might want to check your refractometer as well. They should be calibrated too, but one quick way you can check to see if it is calibrated is by testing your RO water with your refractometer. It should read at 0 because there is no salt. This doesn't mean you calibrate it using RO water though.If it is not reading the RO water at 0, then grab some calibration fluid. If it were me, I would just stick with the refractometer from BRS. Regardless of which you want to use, the key is consistency, so even if you're a bit off, it should be ok.

 

[MuscleBobBuffPants]

You might want to check your refractometer as well. They should be calibrated too, but one quick way you can check to see if it is calibrated is by testing your RO water with your refractometer. It should read at 0 because there is no salt. This doesn't mean you calibrate it using RO water though.If it is not reading the RO water at 0, then grab some calibration fluid. If it were me, I would just stick with the refractometer from BRS. Regardless of which you want to use, the key is consistency, so even if you're a bit off, it should be ok.

Oh yeah I do. I use the BRS calibration fluid and I check the calibration of the refractometer very often. Before each test I do. It’s really easy to just do a quick check before I actually check my water.

 

[Max_nano]

Have you been cleaning the Hanna with RO after using it? I always rinse with RO to put it away saltless and to check that it reads 0 in RODI

 

[MuscleBobBuffPants]

Have you been cleaning the Hanna with RO after using it? I always rinse with RO to put it away saltless and to check that it reads 0 in RODI

yup! Shake vigorously in a Bowl of RODI water each time.

 

[DivingTheWorld]

If you want to know 100% without need for calibration:

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

 

[Krully]

Following because I was considering getting a digital checker.

 

[MuscleBobBuffPants]

If you want to know 100% without need for calibration:

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

I was considering this hydrometer during my original refractometer purchase. I was led to believe it was an outdated method by all of the threads I had read through my research. Now it looks like it might be the best option.
Why are hydro meters seen as inaccurate by so many people? You could do a search right now and people call them a terrible Choice. But those reviews are very good.

 

[Reefing_addiction]

If you want to know 100% without need for calibration:

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

I was thinking about getting one of these. Now I think I will

 

[amoore311]

If you want to know 100% without need for calibration:

High Precision Hydrometer

Ensure that your equipment is reading correctly and your aquarium is at the right salinity with Tropic Marin's High Precision Hydrometer. Many tank inhabitants are sensitive even to minor changes of the water conditions. Unfortunately as we've all experienced, salinity reading equipment as...

www.bulkreefsupply.com

Well hold on a minute here. It's not nearly that simple.

First off, if the water is not exactly 78 degrees... you are not getting an accurate measurement. If the water is moving at all, you aren't getting an accurate measurement.
I have that hydrometer, its absolutely massive. I would wager the vast majority of people don't have a vessel the appropriate size to use this device properly lol.

There is a reason just about everyone outside of brewhouses and science labs tossed these things to the wayside a while ago.

 

[MuscleBobBuffPants]

Well hold on a minute here. It's not nearly that simple.

First off, if the water is not exactly 78 degrees... you are not getting an accurate measurement. If the water is moving at all, you aren't getting an accurate measurement.
I have that hydrometer, its absolutely massive. I would wager the vast majority of people don't have a vessel the appropriate size to use this device properly lol.

There is a reason just about everyone outside of brewhouses and science labs tossed these things to the wayside a while ago.

So the perfect solution is not so perfect after all. Haha. If only someone could invent a foolproof way of easily testing salinity.

 

[JKenny]

I was struggling with this myself.

I was at a point where my calibrated readings were Hanna (33.4) , Milwaukee(36), Apex (35.1) and my refractometer (~34). I had my choice of which to believe... Ended up getting the RS hydrometer that, after a temperature correction, agreed with the Apex nearly spot on.

I'm now at a point where I've decided that I'm already in the right neighborhood and that I'll just keep the salinity as consistent as I can.

Good luck in your quest

 

[vtecintegra]

Why are hydro meters seen as inaccurate by so many people? You could do a search right now and people call them a terrible Choice. But those reviews are very good.

It's the plastic swing arm ones that have a bad rap in regards to accuracy. Any bubbles on the swing arm can throw it off.

 

[DivingTheWorld]

I was considering this hydrometer during my original refractometer purchase. I was led to believe it was an outdated method by all of the threads I had read through my research. Now it looks like it might be the best option.
Why are hydro meters seen as inaccurate by so many people? You could do a search right now and people call them a terrible Choice. But those reviews are very good.

Historically most hydrometers were low quality with variable results. These are not. I have a couple of these and have been using them for years. I wasted way too much money in my pursuit of correct salinity. I have an Apex probe, Pinpoint, Milwaukee and multiple refractometers. They all vary, this does not.

 

[DivingTheWorld]

Well hold on a minute here. It's not nearly that simple.

First off, if the water is not exactly 78 degrees... you are not getting an accurate measurement. If the water is moving at all, you aren't getting an accurate measurement.
I have that hydrometer, its absolutely massive. I would wager the vast majority of people don't have a vessel the appropriate size to use this device properly lol.

There is a reason just about everyone outside of brewhouses and science labs tossed these things to the wayside a while ago.

It's actually 77 degrees, but you can use a correction table:

http://www.reefkeeping.com/issues/2004-07/rhf/

I keep my tank at 79.5-79.9, so I use the 79.7 degree conversion. In other words, at 79.7 degrees, if it measures 1.0259, it is actually reading 1.0264.

So for me, I just wait until my tank is at that temp, shut off the pumps and measure, then turn the pumps back on. It takes me all of 1 minute to take the measurement. If you just float it in your tank there is no need for any measurement vessel.

 

[MuscleBobBuffPants]

Historically most hydrometers were low quality with variable results. These are not. I have a couple of these and have been using them for years. I wasted way too much money in my pursuit of correct salinity. I have an Apex probe, Pinpoint, Milwaukee and multiple refractometers. They all vary, this does not.

So what would you recommend I use moving forward? Out of a all your options which do you trust most?

 

[DivingTheWorld]

So what would you recommend I use moving forward? Out of a all your options which do you trust most?

I just got tired of always wondering so I use the TM hydrometer. IMO, that's the only one I trust for sure. The Milwaukee was a close second. I found it generally consistent, but it was always about 1 ppt high if I remember correctly...

 

[NashobaTek]

I prefer the hydrometer that floats, way more accurate than anything else. I have a refractometer as a backup.

 

[NashobaTek]

I prefer the hydrometer that floats, way more accurate than anything else. I have a refractometer as a backup.

 

[92Miata]

Testing a refractometer with rodi tells you almost nothing. They can be off significantly at 35ppt and still read 0 at 0 (or read zero at 10 PPT). Calibration solution is like $8 for a big bottle.


Refractometers get used for things that need way more precision than a reef tank does. Calibrate it (at 35 PPT!)regularly. Use it. Don't worry too much.