What probe do you trust more?

[parrot_coral]

The Hanna benchtop refractometer, used for years. I once didn’t believe my either three probes, so I bought the TM Hydrometer, and the Hanna refractometer’s number is still completely the same with TM

 

[Reef Jedi]

The Hanna benchtop refractometer, used for years. I once didn’t believe my either three probes, so I bought the TM Hydrometer, and the Hanna refractometer’s number is still completely the same with TM

Is that have the same accuracy as the Hanna pen?

 

[parrot_coral]

Is that have the same accuracy as the Hanna pen?

The accuracy of ppt/psu are 1, SG is 0.001. But I believe the read stability and reliability is more important.

 

[Reef Jedi]

The accuracy of ppt/psu are 1, SG is 0.001. But I believe the read stability and reliability is more important.

Interesting! I was eyeballing that as an upgrade item since it seems so handy.

 

[Lifer]

Another Tropic Marin vote. I use a 500 ml cylinder to get readings. Has yet to let me down. Although high temps will wreck the hydrometer. Don’t ask how I found out.

Be very very careful with the Tropic Marin the neck breaks EXTREMELY EASILY!!

 

[Reef Jedi]

Be very very careful with the Tropic Marin the neck breaks EXTREMELY EASILY!!

Good to note, I’m guessing; don’t hold it by the neck

 

[Reef Jedi]

I will say, since hard core calibrating the apex salinity probe. This has been the most accurate it’s ever been in the last 2.5 years.

 

[winxp_man]

I will say, since hard core calibrating the apex salinity probe. This has been the most accurate it’s ever been in the last 2.5 years.

Curious what method you used.

 

[EZReefLife]

I just spent a while calibrating my new Hanna digital salinity pen and also my apex salinity probe.

Hanna = 34.7 ppm

Apex = 35.8

What probe would you trust? I also have a refractometer and just calibrated that. That basically shows right at 35ppm

Can fish or corals tell the difference between these numbers? Or did I just fall down a rabbit hole I don’t need to go down. If I follow the Hanna then I want to slightly increase salinity. But if I follow the apex then I need to go down slightly. If they were closer I feel I wouldn’t be so conflicted.

Overall what would you trust to run your salinity numbers from?

Not sure which to trust. But my plan for my upcoming tank is to get the Tropic Marin hydrometer which needs no calibration and use that to back up either an apex or hydros system probe.

 

[Reef Jedi]

Not sure which to trust. But my plan for my upcoming tank is to get the Tropic Marin hydrometer which needs no calibration and use that to back up either an apex or hydros system probe.

I just ordered one and I’m super curious how closely it will read

 

[mcarroll]

Just because I can see numbers on a screen, can corals or fish even tell the difference with this close of numbers to 35ppm?

Short answer on this point is no.

Arguably the only reason one needs any more accuracy or precision than a plastic swing-arm hydrometer is if they are doing hypo-salinity treatment for some fish disease. That process requires taking salinity down to a level so low that it could harm the fish if you mis-measure and go too low. (1.008 s.g. if I recal correctly.)

In general NOBODY ever does that.

So the need for fancy salinity measurements is overrated.

If you're one of the exceptions who do hyposalinity treatments, then you know what to do now! :)

Otherwise stop overkilling something that's easy-peasy. The only thing that's important is repeatability (ie consistency).