Salinity Questions....

[briangsxr1000]

How much does temp effect salinity? I calibrated my refractometer with water straight form the RO. It is reading a little lower than my new hydrometer. Seems like when I test my water for water changes before it is heated it will read lower also. Any advice is appreciated.

 

[Gary Majchrzak]

temperature has no effect on salinity.

temperature has a huge effect on specific gravity.

although salinity and S.G. are closely related they aren't the same.

 

[xpxdx]

here's a sweet article!!

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


also it's better to calibrate close to the number that you'll be measuring, with a refractometer that would be 35ppt instead of 0.

 

[briangsxr1000]

so when I check my water it will read the same on my refractometer when its 50* or 80*?

 

[Johnny C]

so when I check my water it will read the same on my refractometer when its 50* or 80*?

Most refractometers compensate for temperature fluctuations, so it shouldn't make a difference.

 

[briangsxr1000]

I checked my water 3 times. All 3 times I have different readings. I recalibrate it with pinpoint calibration solution and find it to be off. This is after I just calibrated it a few mins before I checked my aquarium water. I also make sure to clean it off really well also.
I may throw this thing in the garbage and just use my hydrometer....lol

 

[Gary Majchrzak]

pinch the water sample down tight when using the refracto

 

[briangsxr1000]

ok i will give it a shot and see what happens....

 

[Gary Majchrzak]

here's an article that includes a chart for temperature corrections:

http://www.reefkeeping.com/issues/2004-07/rhf/index.php

 

[briangsxr1000]

It is still acting weird. every time i check the tank I get a different reading. It worked great for a few months... even with calibration solution it will read different every time...weird. Maybe it can be replaced under warranty...it is only few months old.

 

[reefboarder]

It has bee my experience that the light you are using when looking thru the refracto makes a difference in clarity of the reading also the angle to which the light is coming thru the glass seems to change readings for example I can move from a level position up 45 degrees and then back to level and you can see the line blur and move slightly. Thats just my experience with my refracto, but you could see if its the same for you.

 

[briangsxr1000]

I am talking a difference in readings form 1.026 to next reading of 1.020... not even close....lol

 

[reefboarder]

Oh thats a big diff maybe shes takin a fall you dont know about

 

[briangsxr1000]

could be... who knows.. Ill talk to the place i bought it form. Maybe they know a trick or can get it replaced for me.... I don't recall ever droping it ever.

 

[reefdogg1107]

could be... who knows.. Ill talk to the place i bought it form. Maybe they know a trick or can get it replaced for me.... I don't recall ever droping it ever.

You don't neccesarily need to drop it for it to be off, check the piece on top that holds the calibration screw is it tight?? That piece holds the mirror that is adjusted by the screw.

 

[briangsxr1000]

yeah it is tight.