Distilled Water - Refractometer

[imfsub12]

Yes just got my first refractometer.. and it says need to calibrate it using distilled water.. where do i get some..

I don't use ro water for my tank.. so what other sources can i get this???

[fromoe]

grocery store in the water aisle

[rbursek]

Use a calibration solution, distilled will make it read low, I beleive it is pinpoint 53 solution. You may want to post this in the chem forum, lost of info there on this subject.

[imfsub12]

but my instructions said distilled water..

NO CLUE to get calibration solution now...

[gsxunv04]

go to a lfs, they should be able to help. if you have one thats calibrated(such as a lfs) you can compare the two. fwiw grocery store sells gallons of distilled water for $.065/ea

[an411]

Yeah don't use water get the pinpoint calibration solution. I used the water and my refractometer was off. The salinity was an 1.015 and the refractometer was reading 1.026. Don't risk it for the 5 bucks buy the calibration solution by pinpoint.

[imfsub12]

my LFS is crap...

[buck50bmg]

Do what the instructions say. You are measuring a fluid with zero salts ( distilled water) or if you think in specific gravity then it will be 1.0.

rbursek- That stuff your talking about is for the pinpoint salinity probe, NOT a refractometer.

[buck50bmg]

<a href=showthread.php?s=&postid=12384502#post12384502 target=_blank>Originally posted</a> by an411
Yeah don't use water get the pinpoint calibration solution. I used the water and my refractometer was off. The salinity was an 1.015 and the refractometer was reading 1.026. Don't risk it for the 5 bucks buy the calibration solution by pinpoint.

Funny I have the pinpoint salinity probe and it measures the same as my refractometer that is calibrated with distilled water......:rolleyes:

[imfsub12]

hmmm.. well i will go get some distilled water like the instructions say...

[spreston]

<a href=showthread.php?s=&postid=12384692#post12384692 target=_blank>Originally posted</a> by imfsub12
hmmm.. well i will go get some distilled water like the instructions say...

You really should use 53ms solution for calibration. With distilled water mine will read almost 10ppt low when compared to the pinpoint solution.

BTW, my refractometer also says to use distilled water.

[spreston]

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

[HowardW]

<a href=showthread.php?s=&postid=12384521#post12384521 target=_blank>Originally posted</a> by buck50bmg
Do what the instructions say. You are measuring a fluid with zero salts ( distilled water) or if you think in specific gravity then it will be 1.0.

rbursek- That stuff your talking about is for the pinpoint salinity probe, NOT a refractometer.




Incorrect.........most of the hobbyist refractometers are made to test brine solutions and not seawater hence they say to use distilled water and set scale to 0 which may give incorrect reading when testing seawater. The correct way to calibrate it to measure seawater is to use the Pinpoint 53.0 mS solution and set to 1.0264

Some refractos will be pretty close if using distilled and set to read 0 however some will be way off, mine was off by .003 using distilled which is quite a bit.

[imfsub12]

Ok i have a cheep platic salt water tester.. the one with the plastic level in it..

.003 don' t think that will make or break me.. as damm its a guess with my old one...

[buck50bmg]

Last time I checked.....brine is saltwater......duh

[buck50bmg]

As long as you have a refractometer with the correct curve you are good

[sirreal63]

<a href=showthread.php?s=&postid=12385104#post12385104 target=_blank>Originally posted</a> by buck50bmg
Last time I checked.....brine is saltwater......duh



Read the article before you do the duh thing...duh. You may just learn that what you thought was correct was in fact wrong. Brine is not sea water and the refraction is different.

Use the pinpoint 53 ms solution and your refractometer will be correct. Not all refractometers are the same...it isn't worth taking the chance when the solution is so cheap.

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

[HowardW]

<a href=showthread.php?s=&postid=12385104#post12385104 target=_blank>Originally posted</a> by buck50bmg
Last time I checked.....brine is saltwater......duh





Incorrect again.........you may want to read this entire article by Randy Holmes-Farley regarding calibrating refractos and it may explain a few things to you.

http://reefkeeping.com/issues/2006-12/rhf/index.php#20

[mbbuna]

i would also recommend using a calibration solution, and its actually pretty easy to make your own.

from the above linked article

1. Measure ¼ cup of Morton's Iodized Salt (about 73.1 g).
2. Add one teaspoon of salt (making about 79.3 g total salt).
3. Measure the full volume of a plastic 2 L Coke or Diet Coke bottle filled with purified freshwater (about 2104.4 g).
4. Dissolve the total salt (79.3 g) in the total water volume (2104 g) to make an approximately 3.65 weight percent solution of NaCl. The volume of this solution will be slightly larger than the Coke bottle, so dissolve it in another container.

[buck50bmg]

Some of you guys really need to get a life

The term brine means water with salt in it
Duhhhhhh Saltwater.

If you read the article you just sent me you will see that a endpoint calibration is OK.
If you want to take one persons take on this subject and follow it blindly with out thinking for yourself then fine, but dont tell people to buy stuff when they dont need it. Heck a .003 difference is nothing!

I was a Sonar Tech in the Navy Submarine force and we used salinity all the time to figure range to a target, we always were monitoring it, and it always swigged far more than .003 from time to time.

Get over the nerdy tweaking and enjoy the hobby

Oh yea even though you use the solution how are you sure that the curve is correct? Did you ever drop the meter? Are you sure it is ATC? If not are you using a calibrated thermometer to make sure????? Did you touch the sample with your bare hands????? Did you get your sample from your sump or the top of the tank or the bottom???? How much flow do you have???? Was your ATO running??? You could go on and on about the little things that will effect salinity......

[buck50bmg]

So you are making sure the fluid is at exactly 77 F right? Even with ATC?

[mbbuna]

all the "duhs" and "get a life" comments are not appreciated. this is an information exchange board so if you cant do that with out the condescending remarks i suggest you refrain from commenting at all.

Oh yea even though you use the solution how are you sure that the curve is correct?

if you calibrate with with a solution that is at NSW levels and you are testing a sample of NSW then the slope is of little consequence. that is the whole reason for calibrating with something like the pinpoint solution. if the slope is off and you calibrate with distilled it can be very far off when testing seawater.

[HowardW]

<<< The term brine means water with salt in it
Duhhhhhh Saltwater. >>>


Nope........a brine solution and seawater are not the same as far as many test instruments are concerned including refractometers.





<<< that is the whole reason for calibrating with something like the pinpoint solution. if the slope is off and you calibrate with distilled it can be very far off when testing seawater. >>>


Exactly!.........many of the marine hobbyist refractos can and will be off as much as .003 - .005 when calibrated to 0 using distilled water which is a very large margin of error and would pretty much defeat the whole purpose of spending money on a refractometer in the first place.

[imfsub12]

ok where can you get this pinpoint solution in CANADA.. don't want usa places.. as duty will be a killer...

[mbbuna]

cant help you with that but you can make your own in 5 minutes with salt and RO water

[JNye]

if i use that recipe to make my own I calibrate to 1.0264? sorry i did not read the article.:confused:

[A.T.T.R]

a .003 difference is huge
1.020 is to low.. 1.026 is ideal
my refractometer calibrated with RODI ( same as distilled) was off by over .005

everything has a range and you try to calibrate in that range
why do you think you use ph solution 7 and 10 instead o 4 and 7 ?

[imfsub12]

CAn i USE Distilled WATER for my water in the home made solution.. ????? should still work..

[mbbuna]

yes you can use distilled. distilled water is purified water just like RO water is purified water, the two are just processed differently

[imfsub12]

sweet have all the stuff here .. just waiting to get a scale to measure right....

if my salinity is high damm !!!!!!!!!!!!!!!!

[JayB1224]

I calibrated my refractometer today with pinpoint 53 solution.
My salinity was +.004 putting my tank @ 1.030.....Holy shnikies!
I was previously using RO water for calibration...never again.....eventhough the directions say to use it.

[E.J. Coral]

I also use distilled water to calibrate my refractometer. I use NSW that I collect myself. It reads 1.026 every time.:D