Salinity ?

[Dmat21]

Hey guys I was wondering what you Think about testing salinity the old-school way with a hydrometer?
i was just gonna leave mine inside the tank so I can just always peak on the salinity through the glass
Do these get the job done?

 

[Biglew11]

Would probably be a bad idea. Floating around the the tank it could break. Being left in the tank it would be prone to algae build up that would probably scew the readings. You would have to turn the pumps off and wait for the water to get completely calm before getting an accurate reading.

 

[Dmat21]

Would probably be a bad idea. Floating around the the tank it could break. Being left in the tank it would be prone to algae build up that would probably scew the readings. You would have to turn the pumps off and wait for the water to get completely calm before getting an accurate reading.

OK but what do you think about hydrometers overall instead of fancy probeOK but what do you think about hydrometers overall instead of fancy probe readers.?

 

[Pistondog]

the cheap plastic ones can be innaccurate.
Someone else has had good luck with this, no moving parts.
https://www.bulkreefsupply.com/high-precision-hydrometer-tropic-marin.html

 

[xxkenny90xx]

the cheap plastic ones can be innaccurate.
Someone else has had good luck with this, no moving parts.
https://www.bulkreefsupply.com/high-precision-hydrometer-tropic-marin.html

Yep agreed! The tropic marine floating hydrometer is spot on. But swing arm hydrometers are usually off by a couple of points

 

[Jib]

You can get a refracometer of Amazon or bulk reef supply cheap. Just make sure to get the calibration solution as well

 

[stanlalee]

I've been using hydrometers for 25 years without issue. I bought a refractometer on Amazon and the package got lost and never delivered (mind you I've ordered weekly on Amazon for 3-4 years and not ONCE have a package lost). That was my sign to stick with the hydrometer. Just follow these rules: keep it clean and don't let salt creep build up in it, check it at tank or near tank temps and make sure no bubbles are on the arm.
What I will switch to is an electronic salinity meter, just haven't gotten around to it.

 

[Brett S]

Personally I would go with a refractometer over a hydrometer. You won’t spend too much more if you compare ones of reasonable quality and the big advantage of the refractometer is that it can work with just a drop of water. This is super helpful when you get new fish and corals. You can just take a drop of water from the bag they come in to see what the salinity of the water they are used to is and see how far off it is from the water in your tank. Trying to do that with a hydrometer is much more difficult because you need considerably more water.

 

[Conchman]

I still run old school, a hydrometer. I do not leave it in the tank...

 

[X-37B]

I have the tropic marin.
95% of the time I use a swingarm cheapo.
The key is to use the floater and then note where 1.0265 is, or whatever you run, on the swingarm. It can be dead on or most likely read high or low to some degree.
That calibrates your swingarm to the correct sg.
Example: 1.0265 reads 1.025 on your swingarm. You now know 1.025 is actually 1.0265.
You can do the same with your refractometer.

 

[jda]

Glass ones are fine. Need to be in stable/stagnant water with no movement. I would not leave it in the tank all of the time.

Swing arms can drift over time. You almost need to check them before every use, so then what is the point?

 

[Ksull72487]

Use the Floating High Precision Hydrometer or a good Calibrated Refractometer that’s kept clean and maintained.

Ditch the Swing Arm. The only swing arm I’d use is an Instant Ocean if I had to use one.

 

[attiland]

+1 for refractometer you have results in 30 sec.

 

[Ksull72487]

+1 for refractometer you have results in 30 sec.

Yup I prefer that method. I know those High Percision Glass ones the floaters are good tho. The refractometer you have to maintain and dial in correctly.

 

[Rp8]

I use both. I have a swing arm for random quick checks during the week. Then I use a refractometer on the weekly full panel tests

 

[Biglew11]

Refractometer or the floating glass hydrometer is great. I avoid the swing arm hydrometers like the plague.

 

[attiland]

Yup I prefer that method. I know those High Percision Glass ones the floaters are good tho. The refractometer you have to maintain and dial in correctly.

Although I check every so often I didn’t have to adjust for months. If yo average out your time to do that is could add extra 3 sec on average.