help with tds and a refractometer question

godlyme

New member
anyone out there near smithtown that can help me test to see if my rodi is working properly. also I am having trouble with my refractometer... for some reason my hydrometers( x4) and the refractometer all register different values...im getting concerned.. anyone know a way to check which is right? im sure the refractometer is more accurate but i want to be 100% positive... thanks everyone
 
A refractometer is well known to be more accurate than a hydrometer. You should know that without proper calibration, you might just be a LOT better off with a hydrometer.
If you are uncertain of your RO/DI output water, you can't use that to calibrate a refractometer.
Salifert actually markets a refractometer calibration fluid (salt water packaged at exactly 32 PPM). I'm not sure it's for sale anywhere, but I have some here. I'm a bit of a hike from Smithtown, though.
 
<a href=showthread.php?s=&postid=9322136#post9322136 target=_blank>Originally posted</a> by bobbbm
I have an RO/DI From purley H2O so I just trust that it's close enough to calibrate it to Zero...


Bob,
Don't take this the wrong way, but unless you have a calibrated TDS meter, you can not tell what quality water you're getting. Bryan is a great guy, and he sells good stuff, but you can't calibrate your refractometer on an unknown solution. You would be far better off seeing if a LFS has the Salifert (or comparable) calibration fluid, or come to my house, and I'll be happy to calibrate it for you. I calibrate mine at most every two months or so. It's not something you have to do weekly or daily.
My TDS meter is part of my RO/DI unit, so I can't help you there.

I don't remember why, but I'm sure I read that distilled water should not be used as a zero calibration fluid (like you can use pure RO/DI), but I don't remember the reason.
 
I don't remember why, but I'm sure I read that distilled water should not be used as a zero calibration fluid (like you can use pure RO/DI), but I don't remember the reason.


Hmmm...I've been using distilled water to calibrate mine???
 
My refractometer says to use distilled water also... But I will bet Larry is 100% right who knows where that water has been or how it was packaged.
 
Bobbbm,
I have a TDS Meter from a Spectrapure unit. Replaced a few months ago when I put on a Max Cap unit. You can have it for $20.00, about 1/2 price.
Vinny
 
I think this (distilled water for zero calibration) is a question for Randy in the Chemistry forum, or Habib in the Salifert forum. Both are Chemists, and can tell you with 100% certainty if I am right, or completely off my rocker ;)
 
<a href=showthread.php?s=&postid=9322737#post9322737 target=_blank>Originally posted</a> by Vinny Kreyling
Bobbbm,
I have a TDS Meter from a Spectrapure unit. Replaced a few months ago when I put on a Max Cap unit. You can have it for $20.00, about 1/2 price.
Vinny

Using a good TDS meter (that one qualifies) on your RO/DI water, as long as you get a TDS reading of ZERO, you can calibrate your refractometer to zero using your RO/DI water.
 
thanks everyone for the suggestions....im going to search online to see if i can find some calibration fluid...as i am not trusting of my ro di unit...i can not tell if the salinity is off or if the water im using is no good..... anyone found a place to buy cal fluid?
 
<a href=showthread.php?s=&postid=9328186#post9328186 target=_blank>Originally posted</a> by godlyme
thanks everyone for the suggestions....im going to search online to see if i can find some calibration fluid...as i am not trusting of my ro di unit...i can not tell if the salinity is off or if the water im using is no good..... anyone found a place to buy cal fluid?


By using a TDS meter, you can tell if your RO/DI is doing what you need it to do.
Calibrating a refractometer aside, a TDS meter is a very worthwhile tool to use in maintaining water quality.
 
<a href=showthread.php?s=&postid=9322737#post9322737 target=_blank>Originally posted</a> by Vinny Kreyling
Bobbbm,
I have a TDS Meter from a Spectrapure unit. Replaced a few months ago when I put on a Max Cap unit. You can have it for $20.00, about 1/2 price.
Vinny

Great I will take it!
 
ok another uestion how do you calibrate a tds meter????I have a new one on my rodi do they come calibrated...I bout the calibration solution 10.0 and 7.1 I think but how can you calibrate a dual tds meter???
 
ok i ordered some cal fluid from the link some one provided from diyreef place....also ordred some other goodies... that will solve the salinity problem i hope...i cant understand why i am getting 5 differeent readings...i mean completely different readings from 4 hydrometers and 1 refractometer.... range goes from .20-.30.... each one has the same reading time and again..its not that each one comes up with different levels...i have rinsed and washed all of them very good also..... BUT can anyone help me out with the TDS readings? anyone near smithtown?
 
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