My salinity is 1.029

[Boxster]

I use my Deep Six Hydrometer and set my tank to Salinity of 1.024. Just got my Refractometer last night and and lo and behold, its reads 1.029. Man, don't ever trust those hydrometer. I lost my yellow tank recently, wondering whether it could be the high salinity killing it.

 

[jamal-188]

My instand ocean hydrometer read 1.025 and my refractometer said 1.028. I'm so glad I got one when I did, I'll never trust those little plastic hydrometers again.

 

[hicmndr]

I had the same issue. My Deep 6 Hydrometer said 1.026, my refractometer said 1.032! I'm slowly bringing down my salinity as a result. Let's just hope that the refractometers are correct...

 

[mrrrkva]

Just as Hicmndr has said. If you find this to be the case, bring it down very slowly!! There are places to get those refractometers for $40 and less. A GREAT investment

 

[reefrunner69]

This is not condescending, some people simply aren't informed it needs to be done...when comparing the two for the first time...have you calibrated the refractometer with RO or distilled water?

 

[Boxster]

Yes, I did and its read 1 for distilled water before I test my tank. Actually, the instruction comes with the refractometer mentioned about the calibration.

 

[hicmndr]

Mine appeared to be perfectly calibrated when I received it. I checked it with RO, and it was spot on. Also, not all refractometers adjust for temperature, so that could be a concern as well. Mine has ATC on it.

 

[reefrunner69]

Actually, the instruction

LOL, I would expect as much from female reefers...but since when do we read the instructions

Like I said before, I was not trying to condescend, simply making certain the instrument was calibrated before you move your salinity

 

[snapcrackler]

Also fellow reefers don't forget........ don't take the water sample from the surface, take it from 6 inches or better below the surface.

When you have a minute and have your refrac in hand, take a sample from the very top and then again from 6 inches down - you will see the difference.

 

[reefrunner69]

When you have a minute and have your refrac in hand, take a sample from the very top and then again from 6 inches down - you will see the difference.

Hmmmm, I've never done that before, will try it

 

[jamal-188]

When you have a minute and have your refrac in hand, take a sample from the very top and then again from 6 inches down - you will see the difference.

Hmmmm, I've never done that before, will try it

Me either, I'll have to check it out

 

[Boxster]

Snapcracker,
How much difference you see? I will defintely try it, that would mean that my hand will get wet.

 

[snapcrackler]

Well when I checked on the surface a few times in the past I went "whoa, my salinity is really high!" and then I dip down 4-6 inches and sure enough it's right on the button at 1.025.

I was getting 1.027 on the surface If I remember right

The "deep six" was purportedly engineered to take samples from 6 inches down where the more accurate readings come from.

What did you guys find with your samples? Any variance?

It could have been all of those zos I was eating too you never know.

 

[Bearfan]

I bought the deep six for this reason. Everything I read said that the surface would always give you a higher false reading.

 

[Boxster]

I did the experiment last night and saw no difference in salinity between 1" down the surface vs 6". Maybe, the refractometer is accurate enough to make the reading constant while those plastic hydrometer will take a better measurement at 6". Just a thought on my part.
I am very eager to wait for more experiment results from the rest. I guess this is important enough for everyone to take another look at their salinity and hopefully we can come up with a consensus.

 

[toddwess]

Also, it is important to remember that the plastic SG meters are calibrated for 77 degrees F. If you're water is at, say, 80 degrees F, you have to make an adjustment to the reading you get on your Deep Six SG meter.

There is a table out there somewhere that tells you the conversions, but I can't find it at the moment. I'll look around and post it here.

Todd

 

[toddwess]

Got this link from ReefRunner69

http://www.algone.com/salinity.htm

So if your water is 80 degrees F and your Deep Six gives you a reading of 1.024, your actual salinity is 1.0264.

HTH,
Todd