reverse osmosis.

Discussion in 'Advanced Growing Techniques' started by xameciffo, Mar 8, 2013.

  1. Can some one sum up pros and cons and possibly how it is so amazing. All I feed my babies and they love it.
  2. pros:

    -filtered, near pure water (no it will not reach 100% purity with the RO machines we buy)
    -wont kill micro-organisms because there is no chlorine or chloramine
    -great to test your soil's pH and ECs with
    -great to flush with (edit: NOT AT THE END OF YOUR GROWING CYCLE. i believe the whole flushing thing is BS. i mean flushing out excess nutrient salts if you accidentally have too many in your soil.)


    -has no buffering capacity, so your soil's pH can rapidly change and your plant will rapidly show symptoms of pH problems. (big con)
  3. Home RO units waste water. To process the water it does filter, it wastes several gallons down the drain for each gallon of filtered water it produces.
  4. Learn your plants..... I use well water with no issues(210 ppm average) I just know what they want.....much cheaper then RO unit, and you'll be a better grower IMO.
  5. Agreed ^^

    I use tap water as well and no ppm meter had a buddy test it 300 out of the tap but I can tell what I need to add or take away by looking at my plants

    Sent from iPhone 5
  6. Personally, for me, it was a huge waste of money. And water! I have well water, pH 8.1, TDS around 320, all sorts of dissolved solids. I garden organically and reuse my soil. I've had no issues with my grow to date and started using well water a year ago. Unless your water is really bad, save your dough, bro.


  7. good layout although i would beg to differ on the PH being a problem since RO water has no buffering capacity like you mentioned, it will tend to not effect the soils PH. you see something with zero buffering capacity cannot effect, in a negative nor positive way, something it does not contain.

    that's the very reason i use RO water because my well water tends to raise my soil/hydro PH easily above 7.5-8.5 if i let it. last time i used my aeroponics unit, i had to constantly add PH down every freaking day, or it would raise far above what i needed, not so with RO, stayed the same with minimal drift.
  8. Whether or not RO is going to be a good choice for a grow is going to mainly depend on the quality of the tap/well water available. If the available water isn't that bad then the added water cost/wastage would be the biggest negative.

    Why can't you just have the RO machine feed from a reservoir that is filled with the tap/well water and have the waste/runoff hose feed back into the supply reservoir?

    RO water has zero buffering capacity so it is very easily influenced and its pH changed. The main problem this has caused for me is when I'm trying to adjust the soil solution pH by running some nutrient solution through the pot, the soil pH is usually more buffered by any salt buildup, so it takes alot of RO to flush them and get the pH to the desired level.

    Most of the problems that RO brings can be solved in some way (added chlorine, bufferes, ect.), but it allows you to precisely control what is going into your plants rootzone which once you get it down is much better than just trusting that your tap/well water is ok.
  9. it depends on your application, because plain RO water will most definitely leech some nutrients out of your medium if watered to the point of run-off.

    if you are feeding your plants about 2000PPM, than buffering capacity would not be as much of an issue.

    but if you are trying to water your 3 week old seedlings with "pure" RO water and you have them planted in peat, than you will most likely run into some issues if this practice is continued.

    plus, the pH of a medium is influenced by what types if cations and anions are contained within, and if the only ones you are contributing to your soil solution are the ones your plant uses (K+, Mg++, Ca++, etc.), your soil pH will become influenced by whatever is left within the medium......and this will all depend on what you are using for your medium - coco naturally runs with a higher pH and peat has a more acidic pH.

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