Old Reviews conductivity meter ?

[Wadmann]

Necessary or not ? what type to get ? What to spend ?

 

[MesaBoogie]

Are you building your own lights ? Not sure what you would need to check conductivity for otherwise. You can get a decent one just to check conductivity for under $30.


Edit: oops I guess bumped an oldie post

 

[Simplicio]

Necessary or not ? what type to get ? What to spend ?

Electrical conductivity meter, tds meter, ppm meter are all pretty much the same thing.
They only differ in what they read out.
Such meters are essential for hydroponics.