ppm of tap water - whats tolerable?

[herbie the love bud]

I am still trying to figure out PPM of what?? Chlorine?? Bromine?? Sodium Chloride?? Fecal Solids?? what?? I don't understand "TDS levels".

Not sure if that was a question or just rhetorical. Yup, you're right. PPM of tap water doesn't mean shit. Doesn't have sticker on the water with "Guaranteed Analysis".

herbie the love bud Reviewed by herbie the love bud on 02-25-2008. ppm of tap water - whats tolerable? is there a cutoff level for ppm of tap water where it shouldnt be used? i use distilled and am wondering if i even have to. Rating: 5

[Mississippi Steve]

Not sure if that was a question or just rhetorical. Yup, you're right. PPM of tap water doesn't mean shit. Doesn't have sticker on the water with "Guaranteed Analysis".

Actually it was a question...having a little chemistry background, and playing around with my own grow, I would like to know what they are talking about.

BTW there are test strips that are available for aquarium water that will give you levels of a dozen chemicals and minerals for just a couple of bucks.

[gainesvillegreen]

Actually it was a question...having a little chemistry background, and playing around with my own grow, I would like to know what they are talking about.

BTW there are test strips that are available for aquarium water that will give you levels of a dozen chemicals and minerals for just a couple of bucks.

Wikipedia - T.D.S.

TDS is Total Dissolved Solids, or the measurement of ions and some other substances dissolved in the water. This is a measurement of the ions/salts in a soution. In your setup, this is basically measuring the amount of fertilizer/material in your water that your plant can/will absorb.

Quote from wiki: "The most common chemical constituents are calcium, phosphates, nitrates, sodium, potassium and chloride."

See the most common constituents? Notice the nitrates for N supply, phosphates for P, and potassium for K? Calcium and magnesium are also fairly common in this application, especially in 'harder' waters.