Digital Refractometers: What's your experience?

[A2dahlberg]

1. What's your experience with Digital Refractometers? Tell us what you like about them! I use one when mixing new saltwater. I like the ease of use and clear read-out.

2. Do you own a digital refractometer and if not would you ever consider using one in the future? I own the Hanna HI98319 unit.

HI98319 Marine Salinity Tester

Designed for Simple Aquarium Salinity Testing Hanna Instruments HI98319 Marine Salinity Tester measures electrical conductivity (EC) to determine the salinity of natural and artificial seawater. Within seconds, the salinity and temperature are measured, and then using the temperature reading...

www.bulkreefsupply.com

I'm new to reefing and purchased one. I love it. I check my tank about 1 or 2 times a week. The real benefit is when I'm making salt water. I fill my 5g bucket 1/2 way with RODI then the day before I put in about 6 1/2 cups scoops of salt. That get my Salinity generally is in the 60s. Then I add the fresh bucket of RODI till it reads 34.8. That water gets tested about 9 or 10 times till it's right on the money. I pour 1/2 of the 5g RODI then add 2 cup measures till I get in the 33.8 range then I add a few plastic bowl till I hit my target. Right on the money every time.

 

[Reef.]

Maybe someone can answer this question for me because I've never looked into it. My hesitancy with the refractometer is that it doesn't look like I can use it a bunch of times in a row. I may check my salinity 20 times while I'm mixing my salt water - how does that work with the refractometer?

Either way, I am totally happy with two hydrometers, which I cross check against each other.

why 20 times? Weight your salt next time you make salt water and you'll be able the salinity near enough correct with just one or two corrects.

 

[Koigula]

I owned a digital refractometer that failed.

A big bright LED bulb in sump room with a VeeGee refractometer is for me. It is clear and precise. Spend the 100 usd instead of 35 and have a lab grade device.

 

[huskyboy]

I recently purchased Milwaukee MA887 digital refractometer. In my past I started with that swing arm hydrometer and it worked great for me as long as I was careful with it. Than I progressed into analog refractometer but I never really liked it. After that I just relied on my Apex and it’s salinity (conductivity) probe. Again I had great success with it. Recently I watched a few videos of Randy & Ryan preaching MA887 as the best thing since sliced bread and I decided to get it. When I received it and calibrated it with included distilled water it would not read test solution accurately. 1.025 test solution reads as 1.027 and I had also ordered 1.026 solution that reads 1.028 SG. So basically it reads 0.002 SG points higher than it should. Problem is there is no way to adjust it to read correctly and both Milwaukee and BRS videos show unit reading reference solution spot on. There is also bunch of reviews that indicate the same exact problem of unit reading 0.002 SG points higher. My own review never got posted on their website either despite the fact it was no different from what I just stated here. That caused me to loose a lot of faith in BRS.

 

[Clownfish_Boy]

What is the advantage of a refractometer over a hydrometer ? My hydrometer gives accurate results without all that calibration that is required by a refractometer.

 

[mike550]

Just to be clear we’re talking about digital refractometers like the Milwaukee right? That’s the only one I know of.

Anyway, I use the Hanna salinity checker HI98319 because it’s just as accurate (if not more so) for a lower price, and easier to use. No interest in a digital refractometer

 

[ebeez]

I have the Milwaukee MA887.. works great and no complaints!

 

[Passedyouby]

For today's QOTD I would like to hear about your experiences with Digital Refractometers! If you don't have experience I would still like to hear your thoughts and if you ever have plans to try one out! Let's talk about it today!



1. What's your experience with Digital Refractometers? Tell us what you like about them!

2. Do you own a digital refractometer and if not would you ever consider using one in the future?

Best buy I've ever made!!!

I have all of the hanna checkers, but the reagent spoils and throws numbers off. I have Apex, but we all know how those probes can get . Had 2 SG testers, and neither matched eight other or anything else. And lastly my refractometer I didn't take very good care of and after a year and a half the adjustment screw started to rust and messed up the results.

Now as for the Milwaukee?!?! Oh man!!! I'm in freaking love. 14months in and that is the one check I actually enjoy!!!

 

[raylinds]

I have a Milwaukee green unit. I test it regularly with 0 and 1.025 calibration solution and it is always spot on and a quick and easy test, so what's not to love?

 

[Pete Witteried]

I don't feel salinity is that critical. If you are off a little bit with salinity it makes little difference. Besides, just because you get a digital reading instead of analog, does not make it more accurate.

 

[rtparty]

Have the Milwaukee and love it.

 

[fryman]

What actual devices did you use?

The same manufacturer (Hanna) of both devices (their digital refractometer in Rev's first post here and their inexpensive conductivity meter) claims the conductivity meter is more accurate (which presumably includes repeatability as part of that specification)

My Orion Model 128 conductivity meter COULD NOT be calibrated, so it never took any time to calibrate. Over the nearly 20 years I used it, it never drifted MORE THAN THE EQUIVALENT OF 0.2 PPT, and never needed cleaning. imo, They only need cleaning if you leave them in the tank water 24/7 (I do not advise that). An RO/DI rinse after each use precludes any need for maintenance.

I will say I am not a fan of conductivity probes on aquarium controllers that are left in the water 24/7. For whatever reason, that seems to lead to many problems.

I do also think it worth upgrading from the cheapest conductivity meters like the Hanna 86822 to better quality devices (like used Orion models on ebay with 4 electrode probes).

FWIW, I've seen quite a few folks complain about accuracy of the Milwaukee digital refractometer.

I don't recall the model conductivity meter I had it was years ago. It was not a small hand-held unit like the hanna I see nowadays. It was a box with bnc-connected probe, basically. I agree probes spending 24/7 in water seem to drift alot.

I know some complain about the Milwaukee but my particular unit seems good. I think there's variation in instruments unit-to-unit, some work great while others are "lemons". But this may happen for any make/model. In the QC lab at work, techs often have a preferred instrument. It's the one that reads accurately every time, passes cal year after year without adjustment. Other identical make/model instruments have issues and need constant adjustment, so techs hate using them.

It's important to at least verify the measurement time-to-time, and most of us only care about 35ppt so any test method with a known 35ppt standard ref solution will work. If I needed to measure other points such as 22ppt I might pay attention to mfg's claimed measurement accuracy. But since I can verify the reading at the exact point I care about I'm not sure why it matters. BTW there is a difference between measurement accuracy and variation. In my industry, accuracy is controlled via calibration while measurement variation (repeatability & reproducability) is assessed using gage R&R. It is possible for an instrument to be accurate yet variable (or vice-versa).

I agree that a conductivity meter is more accurate than refractometer if you need to measure full range, but still believe it is more trouble to cal/verify cal. Refractometers only need a drop, so ref 35ppt solution lasts a long time. Conductivity meters need to cover the probe and so need alot more ref solution.

Manual refractometers require slightly better eyesight and lighting than digital ones.

To each his own, just my opinion.

 

[iMi]

I use a refractometer that I calibrate with a calibration fluid. It's effective, costs less, easy to use and accurate. The digital ones seem like just another thing I need to think about charging or replacing batteries. Seems unnecessary.

 

[CoastieFlo]

I recently purchased Milwaukee MA887 digital refractometer. In my past I started with that swing arm hydrometer and it worked great for me as long as I was careful with it. Than I progressed into analog refractometer but I never really liked it. After that I just relied on my Apex and it’s salinity (conductivity) probe. Again I had great success with it. Recently I watched a few videos of Randy & Ryan preaching MA887 as the best thing since sliced bread and I decided to get it. When I received it and calibrated it with included distilled water it would not read test solution accurately. 1.025 test solution reads as 1.027 and I had also ordered 1.026 solution that reads 1.028 SG. So basically it reads 0.002 SG points higher than it should. Problem is there is no way to adjust it to read correctly and both Milwaukee and BRS videos show unit reading reference solution spot on. There is also bunch of reviews that indicate the same exact problem of unit reading 0.002 SG points higher. My own review never got posted on their website either despite the fact it was no different from what I just stated here. That caused me to loose a lot of faith in BRS.

I have the same exact issue, thought I was doing something wrong but I followed instructions and its still .002 off. Even confirmed it with my LFS. I normally don't complain too much, but BRS is simply a business that hypes a lot of stuff for a buck.

 

[huskyboy]

The fact that last two posted reviews along with mine that was never approved and posted state the exact same problem made me wonder if there was a bad batch of those devices. And how many more people weren’t allowed to post their review?

 

[a hill]

1. What's your experience with Digital Refractometers? Tell us what you like about them! I use one when mixing new saltwater. I like the ease of use and clear read-out.

2. Do you own a digital refractometer and if not would you ever consider using one in the future? I own the Hanna HI98319 unit.

HI98319 Marine Salinity Tester

Designed for Simple Aquarium Salinity Testing Hanna Instruments HI98319 Marine Salinity Tester measures electrical conductivity (EC) to determine the salinity of natural and artificial seawater. Within seconds, the salinity and temperature are measured, and then using the temperature reading...

www.bulkreefsupply.com

I completely agree. for me the best part is less mess of dripping water.

I’m manually topping off at night and this makes it easy to check before and after.

-Andrew

 

[ss30]

I use a D&D refractometer and it does what I want, don't see the point of having a digital one.

 

[SeahawkMom]

Just got the Hanna salinity checker HI98319 to replace my refractometer and so love it! Love the thermometer along with it. Quick, simple, accurate and easy to read. Super easy calibration.

 

[-XENOMORPH-]

Yes I do own a digital Refractometer. (Hanna)
Im 3 years in and my path was the typical. first, a hydrometer. Hydrometers are HORRIBLE and inaccurate. I then moved to a hand held Refractometer. Meh... I was squinting everytime. Then moved to a used Milwaukee digital. Great compared to what I was using before. Hahhaha. And I am currently using a Hanna pen. LOVE IT!!! I just calibrate monthly. Love love love it. Hanna Hanna hanna. Did I mention I love them?

 

[DrewBR]

Not stricly a digital refractometer but I own a Mantis conductivity salinity checker. I didnt intent on getting one but I'm upgrading reefs and I got the chance to get it for cheap. It's miles appart from any other salinity measuring equipment I have. It's easy, quick and even if it needed constant calibration to give accurate results (it didnt need any yet) it would still be a great tool for WCs