Salinity Testing Issue - Please Help!

[Fish Fan]

Hey guys!

I think this is the best section to ask this, RHF please move if appropriate :)

This is one of those very humbling things, I feel as though I’ve made a noob mistake (not that I think of myself as much more), and I’m not sure the best course of action, at least in the short term.

Backstory: I don’t have a typical refractometer currently, but about 18 months or so ago I bought a brand new Milwaukee digital refractometer, and I loved it. I calibrated it with distilled water and confirmed with prepared 35 ppt calibration fluid that came with the Milwaukee refractometer, and never gave it much more thought. It has been pointed out to me that it’s not the most accurate option we have, but the darn thing is so convenient, I loved using it, and I assumed it was good enough for what I was doing. At the time, I had two small tanks with some simple Zoas, shrooms, and gorgonians. I continued to occasionally recalibrate with distilled, but I neglected to confirm with a 35 ppt standard. And admittedly, I hadn’t recalibrated it at all in some time now.

More recently, I started a new 25 gallon, and wanted to try some stony corals. I ordered a small batch of frags from Tidal Gardens, delivered yesterday. I decided to test the water the frags came in, and with my Milwaukee they were in 38 ppt water. That seemed odd to me, I would think a place like Tidal Gardens would be right on with salinity, and certainly not high. So right there I started to doubt my Milwaukee. But in the interest of time, I started to slowly acclimate the corals to my tank water.

I also have a Hanna HI98319 Salinity Checker that I got used, if that’s important (perhaps it was incorrectly stored??). I calibrated the Hanna using Hanna’s 35 ppt packets (also came used, but sealed and not expired). I recalibrated the Milwaukee with distilled water. Now when I test my tank water, the Milwaukee reports 33 ppt and the Hanna reports 36.1 ppt. I’ve repeated both tests several times.

What’s really puzzling is that I poured a freshly opened Hanna 35 ppt packet on the Milwaukee, and the Milwaukee is reading that as 25 ppt. I did it three times, each time 25 ppt.

So what gives, and what do I do from here? Sadly, I believe I have frags dying in less than 24 hours, which may be due to other factors, but I have to believe this salinity testing confusion is the root of much of my troubles here :disappointed-face:

Would you be more likely to trust either of the two devices here more than the other?

Yes, I know I need a standard, and yes I’m going to order the TM glass hydrometer and a 500 mL graduated cylinder (should have had one on hand long ago), but that won’t be here until next week, likely. I do like the option of an analog standard that does not need special storage or calibration, and I can use the graduated cylinder to make Randy’s DIY 35 ppt standard solution going forward.

I think my choices right now are:

• Trust one of my two salinity testers
• Run 5 minutes to the pet store near me and grab a swing arm hydrometer
• Drive the 40 minutes or so each way to have a real LFS test the water
• EDIT: I have a PetCo near me that stocks the Imagitatrium refractometer

And, I feel like an idiot, I strongly believe that salinity is the number 1 parameter to stay on top of, and now this.

What would you guys do? Any help would be greatly appreciated! Thank you in advance!

 

[Pistondog]

I feel safe with milwaukee or vee gee after checking with Randys diy cal fluid. I made a liter to reduce measurement error when weighing salt.
Milwaukee always reads 0.001 high. Have to wait a couple of minutes with Milwaukee for tank water sample to get to ambient for best results.

 

[Fish Fan]

I feel safe with milwaukee or vee gee after checking with Randys diy cal fluid. I made a liter to reduce measurement error when weighing salt.
Milwaukee always reads 0.001 high. Have to wait a couple of minutes with Milwaukee for tank water sample to get to ambient for best results.

Thank you for your help here!

I know the Vee Gee refractometer you’re talking about, but unfortunately I don’t have one. I do love my Milwaukee, but after considering my situation further, I'm starting to lean towards the Hanna as being closer to right on.

Consider, the Hanna is reading 36 ppt, and my Milwaukee is reading 33 ppt, a difference of 3 ppt.

I've been mixing my tank’s water to 35 ppt on the Milwaukee, and then when I tested the water from Tidal Gardens my Milwaukee read 38 ppt - a difference of 3 ppt. <Hmmmmm…..

I’m starting to think the Milwaukee is reading about 3 ppt south. Does that seem possible? I so wish I still had some of the Tidal Gardens water to test with the Hanna. I can try to make Randy’s DIY 35 ppt standard solution, but I don’t have a graduated cylinder. I do have a decent, kitchen level gram scale.

 

[Bartanto]

Ug. Sucky situation. I use my Milwaukee as the standard then occasionally check w/ Hanna wand and refracto. Trend tracking w/ Apex conductivity probe. Milwaukee is always on point IME. Sorry, not much help.

 

[Fish Fan]

Ug. Sucky situation. I use my Milwaukee as the standard then occasionally check w/ Hanna wand and refracto. Trend tracking w/ Apex conductivity probe. Milwaukee is always on point IME. Sorry, not much help.

Yeah, this stinks, but I should have know better, I should have had something to compare the Milwaukee to. As much as I hear most people like them, it's not entirely possible mine has gone out of whack, though it's never really been driven hard or mistreated. Thanks for your help!

 

[KStatefan]

What’s really puzzling is that I poured a freshly opened Hanna 35 ppt packet on the Milwaukee, and the Milwaukee is reading that as 25 ppt. I did it three times, each time 25 ppt.

The Hanna packet is a conductivity standard and will not work for a refractometer

Make your own standards using Randy's recipes

 

[Pistondog]

Thank you for your help here!

I know the Vee Gee refractometer you’re talking about, but unfortunately I don’t have one. I do love my Milwaukee, but after considering my situation further, I'm starting to lean towards the Hanna as being closer to right on.

Consider, the Hanna is reading 36 ppt, and my Milwaukee is reading 33 ppt, a difference of 3 ppt.

I've been mixing my tank’s water to 35 ppt on the Milwaukee, and then when I tested the water from Tidal Gardens my Milwaukee read 38 ppt - a difference of 3 ppt. <Hmmmmm…..

I’m starting to think the Milwaukee is reading about 3 ppt south. Does that seem possible? I so wish I still had some of the Tidal Gardens water to test with the Hanna. I can try to make Randy’s DIY 35 ppt standard solution, but I don’t have a graduated cylinder. I do have a decent, kitchen level gram scale.

Get a 2 quart pitcher with liters on 2nd side.

 

[IceNein]

Is there any reason you're avoiding using a refractometer?

If eyesight is a concern, almost all of them have a focus adjustment, like binoculars, so you can take your glasses off, adjust until it is in focus, and then you're good to go.

 

[exnisstech]

My Hanna always reads 0.002 low when calibrated with their solution. What might be best to get you by for now is make some of Randy's calibration fluid using table salt, be confident it is 35ppt and dip the Hanna in and see what it reads. What ever it reads assume that number is 35ppt and use that number for now.

I know veegee is the shizle for refractometers but my cheapo Amazon one marked ATC has been fine for over 8 years.

 

[A_Blind_Reefer]

The accuracy of the Milwaukee is 2ppt I believe, so there’s that to consider. I have full faith in my Milwaukee, and I’m severely visually impaired so I have to as I could never read a traditional refractometer. I kinda went through a similar experience and luckily found a fellow reefer on r2r that came over with their tester to verify mine as I was a bit nervous that something was off. I will say that any residual salts left on the eye, even under the chrome cover, can affect readings as they will redissolve when liquid is applied. Also, the little squeeze dropper can accumulate salts over time. I use a tradition syringe now just so I can feel confident that I’m fully cleaning it after use. I also rinse the eye with ro (drinking water faucet at the sink) after each use. I once disassembled the tester and was amazed just how much salt had built up under the chrome lens cover.

 

[Miami Reef]

Despite the claimed accuracy of Milwaukee (+/- 2 ppt), I find it spot on.

Dissolve 3.65 grams of sodium chloride (Morton Iodized) in 96.35 grams (mL) of purified freshwater to make a 35 ppt or 1.0264 sg refractometer standard.

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

 

[Sophie"s mom]

The accuracy of the Milwaukee is 2ppt I believe, so there’s that to consider. I have full faith in my Milwaukee, and I’m severely visually impaired so I have to as I could never read a traditional refractometer. I kinda went through a similar experience and luckily found a fellow reefer on r2r that came over with their tester to verify mine as I was a bit nervous that something was off. I will say that any residual salts left on the eye, even under the chrome cover, can affect readings as they will redissolve when liquid is applied. Also, the little squeeze dropper can accumulate salts over time. I use a tradition syringe now just so I can feel confident that I’m fully cleaning it after use. I also rinse the eye with ro (drinking water faucet at the sink) after each use. I once disassembled the tester and was amazed just how much salt had built up under the chrome lens cover.

WOW! IT never occured to me about salt getting under the chrome. I will now be checking mine out. I also clean it with RO water after each use.

 

[Fish Fan]

The Hanna packet is a conductivity standard and will not work for a refractometer

Make your own standards using Randy's recipes

Thank you, I should have realized that.

 

[Fish Fan]

Is there any reason you're avoiding using a refractometer?

If eyesight is a concern, almost all of them have a focus adjustment, like binoculars, so you can take your glasses off, adjust until it is in focus, and then you're good to go.

I guess no particular reason, I used to have them, but as I get older I definitely don’t like to squint at things to see them. The Milwaukee was just so easy with the digital readout, I got hooked on it lol!

 

[Fish Fan]

The accuracy of the Milwaukee is 2ppt I believe, so there’s that to consider. I have full faith in my Milwaukee, and I’m severely visually impaired so I have to as I could never read a traditional refractometer. I kinda went through a similar experience and luckily found a fellow reefer on r2r that came over with their tester to verify mine as I was a bit nervous that something was off. I will say that any residual salts left on the eye, even under the chrome cover, can affect readings as they will redissolve when liquid is applied. Also, the little squeeze dropper can accumulate salts over time. I use a tradition syringe now just so I can feel confident that I’m fully cleaning it after use. I also rinse the eye with ro (drinking water faucet at the sink) after each use. I once disassembled the tester and was amazed just how much salt had built up under the chrome lens cover.

Thanks for your reply! I do know that the Milwaukee is not the most accurate tool w have as hobbies, but it’s so darn easy to use. I do know that the lens has to be cleaned well after each use.

Interesting about the salt getting under the lens. Mine looks to be perfectly fine, but I have personally seen others that developed rust around the edge of the pan. Maybe something to watch for.

Thanks again!

 

[Fish Fan]

Despite the claimed accuracy of Milwaukee (+/- 2 ppt), I find it spot on.

Dissolve 3.65 grams of sodium chloride (Morton Iodized) in 96.35 grams (mL) of purified freshwater to make a 35 ppt or 1.0264 sg refractometer standard.

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

Thank you for your help! Yes, I’m going to try to make Randy’s standard here shortly. I may have to double that as my humble kitchen scale doesn’t go to hundredths of a gram, but I’ll do my best to come as close as I can.

 

[Fish Fan]

Guys, should I go ahead and order the TM glass hydrometer? I wouldn’t get here for a few days to a week, but going forward I think this would be best as it needs no special storage or calibration. Would you guys agree?

 

[BryanM]

Hey guys!

I think this is the best section to ask this, RHF please move if appropriate :)

This is one of those very humbling things, I feel as though I’ve made a noob mistake (not that I think of myself as much more), and I’m not sure the best course of action, at least in the short term.

Backstory: I don’t have a typical refractometer currently, but about 18 months or so ago I bought a brand new Milwaukee digital refractometer, and I loved it. I calibrated it with distilled water and confirmed with prepared 35 ppt calibration fluid that came with the Milwaukee refractometer, and never gave it much more thought. It has been pointed out to me that it’s not the most accurate option we have, but the darn thing is so convenient, I loved using it, and I assumed it was good enough for what I was doing. At the time, I had two small tanks with some simple Zoas, shrooms, and gorgonians. I continued to occasionally recalibrate with distilled, but I neglected to confirm with a 35 ppt standard. And admittedly, I hadn’t recalibrated it at all in some time now.

More recently, I started a new 25 gallon, and wanted to try some stony corals. I ordered a small batch of frags from Tidal Gardens, delivered yesterday. I decided to test the water the frags came in, and with my Milwaukee they were in 38 ppt water. That seemed odd to me, I would think a place like Tidal Gardens would be right on with salinity, and certainly not high. So right there I started to doubt my Milwaukee. But in the interest of time, I started to slowly acclimate the corals to my tank water.

I also have a Hanna HI98319 Salinity Checker that I got used, if that’s important (perhaps it was incorrectly stored??). I calibrated the Hanna using Hanna’s 35 ppt packets (also came used, but sealed and not expired). I recalibrated the Milwaukee with distilled water. Now when I test my tank water, the Milwaukee reports 33 ppt and the Hanna reports 36.1 ppt. I’ve repeated both tests several times.

What’s really puzzling is that I poured a freshly opened Hanna 35 ppt packet on the Milwaukee, and the Milwaukee is reading that as 25 ppt. I did it three times, each time 25 ppt.

So what gives, and what do I do from here? Sadly, I believe I have frags dying in less than 24 hours, which may be due to other factors, but I have to believe this salinity testing confusion is the root of much of my troubles here :disappointed-face:

Would you be more likely to trust either of the two devices here more than the other?

Yes, I know I need a standard, and yes I’m going to order the TM glass hydrometer and a 500 mL graduated cylinder (should have had one on hand long ago), but that won’t be here until next week, likely. I do like the option of an analog standard that does not need special storage or calibration, and I can use the graduated cylinder to make Randy’s DIY 35 ppt standard solution going forward.

I think my choices right now are:

• Trust one of my two salinity testers
• Run 5 minutes to the pet store near me and grab a swing arm hydrometer
• Drive the 40 minutes or so each way to have a real LFS test the water
• EDIT: I have a PetCo near me that stocks the Imagitatrium refractometer

And, I feel like an idiot, I strongly believe that salinity is the number 1 parameter to stay on top of, and now this.

What would you guys do? Any help would be greatly appreciated! Thank you in advance!

I have had difficulty with my Milwaukee as well. I've tried RODI water, distilled water, zero it before each use, no luck, it has been very inconsistent for me. As such it has been sidelined and I use a refractometer.

 

[Fish Fan]

I have had difficulty with my Milwaukee as well. I've tried RODI water, distilled water, zero it before each use, no luck, it has been very inconsistent for me. As such it has been sidelined and I use a refractometer.

Thanks for your help here! Yes, I'm beginning to think that my Milwaukee may be a bit of a dud compared to others.

 

[JumboShrimp]

When your glass hydrometer comes, check you Milwaukee for "consistency." Even if it is not spot-on "accurate", at least if it is "consistent" you will know what mental adjustment (+|-) to make, right? (I love the convenience of my Milwaukee; plus mostly I run FOWLR tanks, so the salinity level is much less of a big deal.)