refractometer

[edd59]

if my sybon refractometer is calibrated with 35 ppt solution is it posible to still give a false reading.
reason i ask, i bought fish from 2 different sources and there water tested 30 ppt and my water 35 ppt. i called 1 source, said his water is 35. could it be defective. i was going to order a hydrometer.

 

[Reef By Steele]

How fresh is your calibration solution. If it has evaporated it could be affecting your calibration. I would get a cheap swing arm and do some comparisons, plus you could go to the store and try their water to see if it reads the same on theirs as yours. I have a refractometer and a Hanna digital and intermix them to try to ensure they are not getting out of whack.

 

[Kristopher Conlin]

If it's freshly calibrated with a new solution that hasn't been left open it should be reading accurately.

Are you allowing the calibration solution 45 seconds to temperature adjust?

 

[edd59]

If it's freshly calibrated with a new solution that hasn't been left open it should be reading accurately.

Are you allowing the calibration solution 45 seconds to temperature adjust?

about 1 year old, always closed..
both at room temp. i didnt inquire so it could be theres is not calibrated.

 

[redfishbluefish]

How old is the refractometer? The one thing that could give you a funky reading is the hinged cover plate not freely falling on the angled prism portion. A little WD40 will solve this issue. Check out this post:

Lubricate Your Refractometer

 

[edd59]

How old is the refractometer? The one thing that could give you a funky reading is the hinged cover plate not freely falling on the angled prism portion. A little WD40 will solve this issue. Check out this post:

Lubricate Your Refractometer

that is one of the problems but i do hold it down. hinges are sticky despite lubricating. i'll try taking out the pins and cleaning/lubricating. its about 10 years old so could be time for a new one although i dont know how it works so dont know what can go wrong.

 

[redfishbluefish]

I've found that simply lubing the pins and then moving the hinges back and forth, it loosens them up.

 

[Fritz05]

I only trust my Tropic Marin hydrometer, even though it is harder to use.

 

[edd59]

I've found that simply lubing the pins and then moving the hinges back and forth, it loosens them up.

i tried many times with wd and oil. i'll try knocking the pins out.

I only trust my Tropic Marin hydrometer, even though it is harder to use.

i think your right. thats what i was going to get to check it. they dont lie

 

[dadnjesse]

It's very common for these places to keep their livestock in lower Salinity than 35ppt.

 

[Randy Holmes-Farley]

if my sybon refractometer is calibrated with 35 ppt solution is it posible to still give a false reading.
reason i ask, i bought fish from 2 different sources and there water tested 30 ppt and my water 35 ppt. i called 1 source, said his water is 35. could it be defective. i was going to order a hydrometer.

What 35 ppt solution?

 

[edd59]

brightwell 35 ppt

 

[Randy Holmes-Farley]

brightwell 35 ppt

I personally don’t have high confidence in Brightwell, but against an unknown lfs, it’s impossible to say which, if either, is more accurate.

 

[edd59]

I personally don’t have high confidence in Brightwell, but against an unknown lfs, it’s impossible to say which, if either, is more accurate.

which solution would you recommend? i know you have your own recipe but too lazy

 

[Randy Holmes-Farley]

I’ve not paid enough attention to which brands seemed best and I’ve never seen any study of them. There are some oceanography standards I’d certainly trust, but they aren’t ordinary hobby items.

P-Series

P-Series IAPSO Standard Seawater (S=35), the main single-point standard for salinity measurements.

osil.com

 

[edd59]

I’ve not paid enough attention to which brands seemed best and I’ve never seen any study of them. There are some oceanography standards I’d certainly trust, but they aren’t ordinary hobby items.

P-Series

P-Series IAPSO Standard Seawater (S=35), the main single-point standard for salinity measurements.

osil.com

thanks