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rogergolf66
01/10/2008, 09:10 PM
does anyone have a way to calabrate a refractometer?

if you do and you are coming to the meeting can you bring it? I would be glad to pay what you need. I checked marine depot with no luck. I also check the LFS and no luck.

I just got some stuff from a LFS and my refractor is reading 1.021 on there water and 1.026 on mine. I hope the reading on my meter is right or my salinity is way to high.

The item I got were coral so there salinity should not have been low. I know that most stores keep there fish tanks low but hope not coral tanks.

Roger

hexedagain
01/10/2008, 09:14 PM
What does it read if you test RO water?

SoundsFishy2me2
01/10/2008, 09:20 PM
Like hexedagain says, use some rodi water and adjust to 0.

drosen
01/10/2008, 09:29 PM
One thing however is your refractometer temperature compensating or not? Also I assume its not a BIX so only thing to do for accurate calibration is to change the temperature to the base setting of your model - most are calibrated to 68 deg F. So your Ro water should be at 68 F. Can do that by placing in the fridge for a few minutes.

drosen
01/10/2008, 09:35 PM
Here is probably the best resource I have found on Refractometers, types, science, etc.

http://reefkeeping.com/issues/2006-12/rhf/index.php

enjoy!

bigt0706
01/10/2008, 10:28 PM
use the calibration fluid from pinpoint for there monitor way more acurate and it usally only 4-8 dollars shipped to your door

rogergolf66
01/11/2008, 12:15 AM
thanks

I have the RO in the fridge cooling now.

Roger

mflamb
01/11/2008, 06:47 AM
RO water is not the BEST way to calibrate the refractometer.
Like Tony (bigt0706) said, get some calibration fluid from Pinpoint and calibrate it. You want it to be accurate at 1.026, not 1.000
About a year ago, I bought a case of it and spread it around, someone may still have some.

poknsnok
01/11/2008, 07:05 AM
on my refractometer's manual it says to use distilled water an calidrate to 1.00.. i recently checked it and it was fine.. but you do want it to be accurate at 1.026

poknsnok
01/11/2008, 07:25 AM
after further review I will be getting some calibration fluid for my refractometer :)

rogergolf66
01/11/2008, 07:55 AM
<a href=showthread.php?s=&postid=11573545#post11573545 target=_blank>Originally posted</a> by poknsnok
after further review I will be getting some calibration fluid for my refractometer :)


where do you get it? I checked Marine depot and the LFS already.

Roger

poknsnok
01/11/2008, 08:20 AM
premium aquatics has it

mflamb
01/11/2008, 08:27 AM
You can order it direct from American Marine Inc., makers of Pinpoint products. It's $5.00 per bottle plus shipping.

rogergolf66
01/11/2008, 08:46 AM
<a href=showthread.php?s=&postid=11573835#post11573835 target=_blank>Originally posted</a> by mflamb
You can order it direct from American Marine Inc., makers of Pinpoint products. It's $5.00 per bottle plus shipping.

thanks

till then should I do the ro calibration. I fell asleep after I put the RO water in the fridge

drosen
01/11/2008, 09:02 AM
You need to do both to check your calibration for shift and slope errors. BTW - when you use the pinpont solution only - it calibrates to 35 ppt.

mflamb
01/11/2008, 09:15 AM
<a href=showthread.php?s=&postid=11574023#post11574023 target=_blank>Originally posted</a> by drosen
BTW - when you use the pinpont solution only - it calibrates to 35 ppt.
35 ppt equals 1.025 @ 76 degrees fahrenheit.

bigt0706
01/11/2008, 09:29 PM
thank u mike for chimming in on this one i find when calibrating with ro u get a mixed reading it also depends on the quality of the refractometer