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To RO or not RO

Discussion in 'Marijuana Hydroponics' started by sopappy, Jan 15, 2017.

  1. Jan 15, 2017 #1

    sopappy

    sopappy

    sopappy

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    city water is 70 - 90ppm pH 7.8 - 9

    I like the idea of not needing so much pH down but I read two disturbing things:

    RO water is bad for a pH probe so how do I measure ppm (one probe for both)?

    also read to add back tap water (can't find it now)
    ***? my water is 70, I reduce to 0 and add back in 50 of the **** I just filtered out? I'm buying RO to get rid of 20ppm?
     
  2. Jan 15, 2017 #2

    Grower13

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    70-90 is pretty low......... why the big range for ph?..... with ppm that low I'd upgrade elsewhere
     
  3. Jan 15, 2017 #3

    Lesso

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    Some areas have older iron based water pipes. The ph is raised as to not have acidic corrosive reactions happen and degrade the pipes. Typically it wont range that much, however if you are measuring it at different temps then you will get different readings.
    I use ro but my ppms are 220 coming in with a ph of 8.5. I dont ever add back the tap water either. I dont know why you would. Ph is the biggest challenge in hydro. Ph is also the most common cause of problems in hydro. I couldnt get it under control until i switched to ro water. So i say yes ro
     
  4. Jan 15, 2017 #4

    Kraven

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    I have found my drift from 5.7 to 6.2 will be more steady and take about a week using R/O...only bad side is that I have to add back the Ca/Mg so using R/O basically costs me $1 a day. Before R/O I was 302ppm @ 7.2 pH now with R/O I'm 0ppm @ 6.4, sometimes I have to add SiO2 or pH up to raise the pH after adding nutes.
     
  5. Jan 15, 2017 #5

    Growdude

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    They say to do this so there is no cal/mag issue, most recommend using a cal/mag supplement when using RO water.
     
  6. Jan 15, 2017 #6

    sopappy

    sopappy

    sopappy

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    ****, yup, better lights, I was thinking that too but 70-90 is not that low when I'm limited to 500pm max with my shitty lights right now.
    In early veg, I'm what? 200 and half of that is 90ppm tap water.... I can see where 200 all nutes would be better. **** yellowing, they scream for calmag and that's 50ppm right there, only room for 110 nutes.
    Also, if the RO doesn't have much to do with only 90ppm, I'm thinking the cartridges will last much longer.
    City publishes 8.4 - 8.8 ... I often see 9.0 (winter???)
    Can't be good pH downing that to 5.7 every time....
    Waste water is not a concern so I'm going for it

    aside... without the bubblers, my pH has been steady but I broke down and added ONE stone to each rez....
    if my pH is nutty tonight ... out they come
     
  7. Jan 15, 2017 #7

    sopappy

    sopappy

    sopappy

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    What do you add if you don't add (5.7ph'd) tap water? If you don't add anything, your solution will become more concentrated with nutes. I check my levels every day... the 4 rezs usually drop about 1 - 4 litres a day.... I add that back in from the original 5.7 water I used to mix the nutes and THEN I check the ppms.

    yup, I ordered the RO, a hundred bucks doesn't get me much more light :-(
     
  8. Jan 15, 2017 #8

    sopappy

    sopappy

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    hey Kraven! thanks for popping by,
    I've finally twigged to the cal/mag thing and understand it. (ha!)
    but what I'm not getting is why some (RO) growers add tap water
    I hate to plug this guy (but there is plenty of good stuff):
    https://www.youtube.com/watch?v=fb3RBNuVJlk&t=80s
    1:50 what the **** is he on about? I don't want to RAISE my pH but I do want to stabilize it.
    Sounds like you say it will happen but if it does, I can use pH up instead of tap water which I feel better about.
     
  9. Jan 15, 2017 #9

    sopappy

    sopappy

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    I haven't got my RO yet but I'm already using cal/mag and was using epsom salts before this, seems it's a given in hydro, makes me wonder why it's not in the nutes already?
     
  10. Jan 15, 2017 #10

    Lesso

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    Cal mag suppliment is a more quantifiable way of adding back cal mag.
     
  11. Jan 15, 2017 #11

    Lesso

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    I add back nutrient solution or plain ro water with a little ph down. My ro water is 6.8 ph. 8 ppm
     
  12. Jan 16, 2017 #12

    sopappy

    sopappy

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    after all my reading, 6.8 seems high
    good and bad with RO, I'm tempted to get a re-mineralize cartridge so I can drink it..... pharma in tap water, that explains Trudeau anyways

    some notes I took:

    removes contaminants arsenic, nitrates, sodium, copper and lead, some organic chemicals, and the municipal additive fluoride.

    and the bummers
    however also removes most mineral particles (including sodium, calcium, magnesium and iron
    does NOT remove volatile organic chemical (VOCs), chlorine and chloramines, pharmaceuticals, and a host of other synthetic chemicals found in municipal water
     
  13. Jan 17, 2017 #13

    pcduck

    pcduck

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    Mine removes chlorines. Don't you have a carbon filter attached to your ro filter?
     
  14. Jan 17, 2017 #14

    sopappy

    sopappy

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    http://www.waterbenefitshealth.com/reverse-osmosis-water.html

    I should have kept reading, they were talking about the RO membrane.
    I have the charcoal cartridge but I have chloramine here, is it a concern? jeeze, another cartridge?
     
  15. Jan 18, 2017 #15

    sopappy

    sopappy

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    forgot to ask about my RO mod, pretty ripped, it was fun, all hooked up
    I wanted to add a bypass to the flow restrictor thingie a la youtube but don't have the parts.
    I did have some air stuff, so that brass T takes membrane output to restrictor and to a 2nd waste tube with a tap on the end, seems like the same thing to me

    jeeze, that picture looks scary with the duplex right below, I must be violating some code there,

    ro.JPG
     
  16. Jan 19, 2017 #16

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    Dank Reaper

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    Your ppm is low for tap.

    Have you mixed up nutes and checked if it has buffered ok and holds?

    That needs to be your biggest concern.


    You should be fine.

    I run r/o at 0ppm so I know EXACTLY what is in my water and what my feed ppm is to the T.


    You should have 0 issues.
     
  17. Jan 19, 2017 #17

    sopappy

    sopappy

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    the water is good but I like that T part myself and it sure is pure
    I have a detector I sit in the bins so they don't overflow, level just quietly sails over it.

    On that, I knew there was waste but man, it's hard to watch. I use it to fill washer and jugs, I'm also doing that flush thing for 2 minutes before using the filtered water.
    I know not to drink after the de-ion as it sucks the calcium out of your bones,
    but I'm thinking this water that passes sediment/carbon and flows over the membrane is fine, gold even.
     
  18. Jan 19, 2017 #18

    sopappy

    sopappy

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    I've seen it as low as 50ppm.
    I don't really understand buffering but I read that adding 10% tap back in is supposed to steady the pH
    That's probably close to 50ppm haha, I'd rather not do that
     
  19. Jan 19, 2017 #19

    pcduck

    pcduck

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    Not sure how or what brand of nutes you use, but most bottled nutes have buffers in them to place the pH at the proper level.
     
  20. Jan 20, 2017 #20

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