Refractometre/PinPoint Salanity monitor/Milwalkee Conductivi

[Willito]

None of them are really necessary, unless your a gear junky then half the fun is calibrating them.

If you have a CA reactor I would say get the pinpoint PH Monitor. Even if you don't I think its the most important. But it also requires the most maintenance.
A refractometer is cool but not as important. I would say it's the least for maintenance as you can calibrate it with RO/DI water.

Are you kidding me, " it's not necessary"? You're in the wrong hobby my friend.

I do run a CA reactor, but my concerns are with the Salanity testing/monitoring equipments, not Ph.

thanks anyways.