Salinity And Warmed Water

[Heywooood]

When do you folks measure your salinity when mixing a new batch of water for a change, when the water is warmed up or when it's room temp?

See this article...
http://www.algone.com/salinity-and-specific-gravity-guidelines-for-the-saltwater-and-reef-keeper

I have generally added salt to room temp water, mixed it thoroughly to 1.025-ish, then heated up to tank temp and then done the change. If I'm reading this article correctly, 1.025 at room temp is really 1.0273 at temp?

 

[sirhc13]

I'm pretty new at this....but the way I've been doing it is I add the approximate amount of salt to a known volume of water add a power head and heater, let it mix and come up to temp, then test salinity and adjust if needed.

 

[kapelan]

what kind of tool are you using?
I'm using refractometer, it's impossible to measure with such precision:

 

[Nighthawk26]

I know this to be the case, and have had arguments with people about it who don't believe. If you have an Apex it's a pretty easy correlation to see cause you will literally see salinity rise and fall as heaters come on and off and waver even 1 degree. I can't speak for all salts, but with red sea coral pro salt it will tell you how much to add based on temp you keep your tank. I add 1/2 cup per gallon. I keep my tank at 77-78 and salinity is always 1.025-1.-26.

 

[Nighthawk26]

To this

what kind of tool are you using?
I'm using refractometer, it's impossible to measure with such precision:

To this point. Refractometers aren't all the same. Some are ATC, some aren't. Some are calibrated at way off temps. Read the manuals, and if needed use a chart to convert from your colder temp to your tank temp. I've read articles in the past that suggest many MANY reefers run their salinity much higher than they believe it is as a result of this reality.

 

[Heywooood]

I use a refractometer, and I've never had my measurements confirmed any other way so I've been under the same conditions since day one. If I read my tank right now it says ~1.025, but according to the chart that would actually be 1.023, which strikes me as low?

 

[Shooter000]

How I do it...
5 gallons of ro water heated to 79 degrees with a power head, then add salt (Instant ocean RC) slowly to avoid precipitation of trace elements, adding salt to quick will bind trace elements together, thus losing them to skimming quicker...as I've been told, I also don't use a refractometer, hydrometer all the way, have never had a problem

 

[Cliff]

I have to calibrate my probe again but this shows the direct correlation of salinity and temp

 

[zoomster]

I do mine similar to @Shooter000.
I did get a refractometer for Christmas but don't want to use it until A- I can get some calibration fluid and check it. And B- I know i can use it with confidence.
Until then, keep on using my hydrometer.

 

[zoomster]

Actually on the topic, anyone know where is the best place / who carries both salinity and 342 tds calibration fluids?

 

[kapelan]

hydrometer or refractometer or just measure tape - they are measurement tools.
All of them has a precision and this precision = 1 division on a rule.
So if we see salinity = 1.025 that really means Salinity between 1.024 and 1.026.

 

[zoomster]

hydrometer or refractometer or just measure tape - they are measurement tools.
All of them has a precision and this precision = 1 division on a rule.
So if we see salinity = 1.025 that really means Salinity between 1.024 and 1.026.

Yep that is very true and can be applied to any measuring device.

 

[scubasteve]

hydrometer you need to rinse out with ro to keep them accurate. salt creep buildup will cause false readings if you dont rinse it. refractometers are more accurate but only when properly calibrated. especially if sps dominant. as for temp most brands specify how much salt per gallons of water to mix properly if temps are at x amount

 

[zoomster]

I wouldn't listen to a thing Scubasteve says.
pretty sure he has forgotten how to mix salt! LOL
Just kidding with ya there Scubasteve! But that is a great point about rinsing to avoid the build up of salt. I keep mine in a tub of RO when not in use.

 

[reef keeper]

I don't think I have ever tested salinity in my tank. My NSW is always 1.025 ish at room temp.

 

[BigReefer]

i do it different i guess I use 5 gallon bucket ... i place 2 cups and a bit of red sea pro salt ... then i use a power head to mix it ... wait 2 days for it to "rest" presay or get to the room temp ... then check it and then do my water change ...

 

[Nighthawk26]

I have to calibrate my probe again but this shows the direct correlation of salinity and temp

1.7- 4 amp. Must be nice! But yes, I see the same correlation. like you also off on the basseline, but you know when it's low or high none the less.

 

[Nighthawk26]

Y

I do mine similar to @Shooter000.
I did get a refractometer for Christmas but don't want to use it until A- I can get some calibration fluid and check it. And B- I know i can use it with confidence.
Until then, keep on using my hydrometer.

It's more than fine to use RO water. Hell Tap water. I've compared all 3, and it will 0 out with all of them.

 

[Nighthawk26]

R

Actually on the topic, anyone know where is the best place / who carries both salinity and 342 tds calibration fluids?

Ray at Reefsupplies.

 

[zoomster]

Oh, so you are saying to just use my RODI water and 0 out the meter to calibrate it?
it is a nice refractometer but, I saw another member had got the same one and neither his or mine came with English inst and my Chinese is pretty rusty!
LOL