TDs too low maybe?

[GreenBean420]

Starting to get everything in place for my next grow and my TDs meter arrived today so couldn't help myself and banged it in some water to measure ppms of my tap water holy s@#t its 71PPM that's low ain't it? Should I be using cal mag in soil now? As I'm moving to coco I'm almost certain I will have to then any info greatly appreciated.

[M_C]

EC is our prefered measurement as PPM has several different scales....

[GreenBean420]

What so the TDS meter is practically useless and I need an ec meter? I thought you could use either ppms or ec and just convert each other?

[M_C]

I thought you could use either ppms or ec and just convert each other?

You can so long as you know which PPM scale you are using... this chart shows some of the popular PPM measurements...



If you want to know more about EC, TDS & PPM, then check out this video

[GreenBean420]

What so the TDS meter is practically useless and I need an ec meter? I thought you could use either ppms or ec and just convert each other?

[M_C]

What so the TDS meter is practically useless and I need an ec meter? I thought you could use either ppms or ec and just convert each other?

I never said that. But you need to know the scale that your PPMs are measured in - see my post above

[Sadface]

Like mc has said TDS are ok but you need to know exactly what TDS meter it is so as you know which scale to use as different manufactures use the various scales mc has shown you...where as if you get a ec meter you just take reading and job done rather than convert using whatever chart is necessary

[Sadface]

I bought a TDS meter and slung it before it ever got used

[Bomber]

Mon the Ec

[GreenBean420]

Thanks everyone I got a 3.99 one off eBay so I'm guessing you get what you pay for at least I can measure the temperature of the water with it because it doesn't say what type of PPM scale it is so I'm guessing I'm going to have to buy an ec meter?