Do Refractometers go bad?

[Enrique797]

Okay, so I'm trying to calibrate my refractometer using both calibration fluid and ro/di water. However, once calibrated if I try to use it again after about an hour some times it is off by 10ppm. Also, once after I calibrated it I hit it on the side with my palm and it was then off ppm.

It seems the calibration mechanism is broken in some way and I need a new one but I've never heard or seen one of these go bad.

Do refractometers go bad?

 

[Neoalchemist]

All i can tthink of is make sure give enough time for temperature of the sample ans the refractometer to equalize. I believe most work best when the temp of the water and the temp of the refractometer are both 77 degrees.

 

[Jeeperz]

My red Sea refractometer would never hold calibration. I had to float it in the tank for half hour and calibrate, then measure right away or it was off. My cheapo from BRS holds calibration but I still check every use.

 

[Neoalchemist]

Other than that, I I guess there could be something wrong with the calibration mechanism. Has the screw ever been removed or possibly over tightened? Either of those could possibly "screw" something up.
Sorry for the horrible pun.

 

[Neoalchemist]

1st post eh. WELCOME TO R2R!

 

[Mical]

Also, once after I calibrated it I hit it on the side with my palm and it was then off ppm.

Do refractometers go bad?

I don't hitting it on the side is a proper means of checking it. You might consider investing in a new one and NOT hitting it. I have an ATC refractometer for about 10 years now, calibrate it 3- 4 times a year with cal fluid no issues.

 

[New&no clue]

Mine stopped working too. I would calibrate it, test my tank water, and then check if it was still calibrated and it wasn’t. I bought a new one and it works great

 

[Cory]

I have one that shows different sometimes. I think its the glass cover. If its not perfectly flat it reads off. The calibration screw is also bad and rusted.

 

[Enrique797]

Thank you all for the feedback and thank you for the warm welcome. I'm glad to hear I'm not the only one whose had a similar challenge.

I'll be replacing it asap.

 

[Slawman]

They can "go bad", break and go out of calibration. If any instrument or test does not return reliable results then you need to go for something else or fix it.

Banging the instrument is not a fix and is a good way to break one.

It is good you picked it up.

 

[Enrique797]

Banging the instrument is not a fix and is a good way to break one.

Exactly, I was not banging the instrument to fix it. I had a suspicion that the meter was losing calibration after being moved or sat down. I was trying to duplicate that by hitting it on the side with my palm. I did not expect that to fix the problem, I hoped it would duplicate it. During my years troubleshooting avionics we called this the "technical tap." lol

 

[redfishbluefish]

The other maintenance thing you need to do with your refractometer is to lubricate the hinges. It's discussed in this link:

Lubricate Your Refractometer

 

[ca1ore]

I had to replace mine after about 10 years because both the calibration knob and hinge corroded to the point that it was unusable. My current one is now approaching 10 years and probably needs replacing soon. Neither of them lost the ability to measure accurately though.

 

[Enrique797]

I ended up getting a new one. Thanks for all the help.