Tap water - Chlorine / PPM / pH

[GregoryJ]

I'm working on growing some lettuce in a NFT system with 4" PVC pipe. My problem is when i change nutrients, I have a difficult time maintaining pH for the first couple days. The roots turn brown, growth stops. Finally get the pH corrected and the new root growth is white, and the lettuce takes off.

I'm wondering if the local city tap water has too many... chemicals! and this alters the pH or damages the roots? After a couple days, pH stabilizes and root growth is good... maybe after the chlorine in the water evaporates?

ideally, I would use a RO system to clean things up, or buy distilled water and add in nutrients. But for now, its just tap water. I use tap water to water my tomatoes and other plants - but they are in soil. So, how much does the - chlorine/flouride/??? whatever else is in our tap water - affect the plants? is there anything to use to neutralize the chemicals in the water - like "start-Right" for fish tanks?

Thanks.

[GpsFrontier]

That's an interesting problem, I don't use tap directly myself. How much water do you need for the reservoir? There are the water machines (usually at grocery stores) that filter the water. It's usually $0.25 a gallon, you just fill your own containers. You may give that a try, and see if the problem disappears. Not sure about fluoride, but chlorine is no good for plants. I believe it's a form of bleach (as in chlorine bleach), and bleach does loose it's potency over a short time when diluted. So that would certainly make sense, but I don't know how much it affects the pH.

You can also place some tap water in a jug and test it right away from the tap. Then check it every day for about a week, and see if the pH changes like you are experiencing in the hydro system during that time. The local water company can tell you what, and how much is in the tap water. But it would be local because it varies a lot from city to city. But none of the chemicals that the water company uses would be any good for the plants. I would defiantly try to get some better quality water regardless.

[Luches]

Originally Posted by GregoryJ

I'm wondering if the local city tap water has too many... chemicals! and this alters the pH or damages the roots? After a couple days, pH stabilizes and root growth is good... maybe after the chlorine in the water evaporates?

The "ch" word, huh? Your nutrients are in fact made of chemicals aren't they? Anyway, chlorine is one of the beneficial (not essential) elements that plants use in small amounts but in bigger than micro nutrients, a bit like Na and Si, etc. Top soils contain an average of 10 ppm of chlorine, up to 80 ppm is borderline and at 100 ppm toxicity starts. I even used to add up to 25-30 ppm of chlorine to my nutrients as Cl misses in my tap water. All is about the dose, as with so many things and all that is related to the "ch" word

There is a bit of a controversy about letting sit tap water overnight to let chlorine evaporate. Most say that in fact some will evaporate, but actually only little.

It doesn't affect your PH, - but if chlorine is introduced through calcium chloride to your tap water, the extra calcium will affect PH and buffer a high PH longer. What the actual problem her is, is always the water hardness. Fluoride would only be present in very small amounts and wouldn't affect plant growth. But here also it gets introduced through calcium fluoride and more calcium.

Than again so called airborne fluorides (from atmospheric pollution) are a serious matter. I guess that's a bit like with sulfur, as S is one of the essential elements in plant nutrition, although it was always considered a dangerous pollutant in the atmosphere.

It's strange though, that your roots alternatively turn brown, growth stagnates - but take off again with white growth of roots a couple of days later. Never seen it and never heard of it in that context of yours.

[garcrob]

I USED TO HAVE A TON OF FISH AND THEY CAN NOT HAVE ANY CHLORINE OR CHLORAMINE OR ANY THING ELE. I USED A CONDITIONER TO NEUTRALIZE THE EXTRAS IN THE WATER.

Aquarium Pharmaceuticals 52C Tap Water Conditinr 16oz 12


THE WATER IN MY TOWN IS REALLY FILLED WITH CHLORENE, YOU CAN ACTUALLY SMELL IT OFF THE WATER. NO JOKE.

SO WHY NOT USE THAT FOR THE PLANTS, IT IS NOT RO WATER BUT IT IS CHEAP AND SHOULD WORK RIGHT???

ANY THOUGHTS?