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how often do I change the water/check pH levels?

Discussion in 'Hydroponic Growing' started by nxk, Aug 20, 2010.

  1. How often should I change my plants water?

    I went out of state for 5 days and left my newly planted seeds in my hydroponics system. I came back yesterday and wasnt sure if they were going to be alive, and they look pretty healthy and both sprouted.


    Also how often should I check the pH levels?
  2. #2 bazzle, Aug 20, 2010
    Last edited by a moderator: Aug 20, 2010
    If you want to do things right and achieve the best results, you should change out your nute mixture every week. Wait a couple weeks after you introduce the plants into the system before you change it out the first time.
    You should check the pH level every day, that is the most important factor in hydro. It needs to be between 5.2 and 6.3, and shouldn't vary more than 0.5 in 12 hours- you don't want to shock your plants with a quick change. Also, if you don't have a ppm meter your pH can help you determine how much nutes to use (your babies are ready for a low concentration nute mixture when the second node appears). If the pH is rising, your plants are using up nutes and you should add a higher concentration. If the pH is dropping, your plant is using more water than nutes and you should add a lower concentration or just water.

    Also, it looks like you may want to move your lights a bit closer to the plants they seem to be stretching up for the light. You want your light as close as possible without burning the plants. The rule of thumb is to place your hand at plant level: if it starts to feel pretty warm or uncomfortable, it is too hot for your plants.

    One more thing: I like to cover up the net pot, especially the rockwool to avoid algae. You can cut a hole in a paper plate for an easy fix there.

    Babies are looking good though :)
    Golbez likes this.
  3. For right now yeah waiting 2 weeks is just fine, and as said above after your babies get bigger weekly changes are key IMO.

    Now in my own opinion, I think between 5.6-6.0 is the boundary most try to keep in, checking daily is ideal for most any system.

    Happy growin!

  4. You're going to find that something that might be standard practice for one grower, is the opposite of what other growers do. Keep that in mind as you find what works best for you and your grow ;)

    You don't have to "change" the water, you can top off during the week with plain, ph'd water and add nutes back as the plants need them.

    IMO, it's important to check ph daily.

    You can cover the top of the rockwool with hydroton :smoke:

    Do you have an air stone in the tub? I'm assuming so, judging by what looks like an air line going through the lid of your set up.

    Also, you may want to light proof the tub / lid otherwise you'll be dealing with algae at some point. I like to use foil tape, it can be purchased at hardware / hydro stores.

    Good luck! :smoke:
  5. #5 trickJames, Aug 22, 2010
    Last edited by a moderator: Aug 22, 2010
    Swap res once per week no exceptions, you'll be pissed off if something as simple as this screws you out of your crop.. just for being lazy.....

    You can top it off with water if it gets low during the week like the guy above me said. Check Ph right after you top off and adjust if you have to.
    Add Ph Adjusters in BABY STEPS. Checking each time you add adjuster. A little goes a long way.
    (make sure you stir good each time you adjust)

    Check PH EVERYDAY. Sometimes it can be stable for days and then get screwy all of a sudden so stay on top of this. You must be vigilant against the PH spike demon!!

    Also clean your res every couple of weeks preferably with Hydrogen Peroxide and a scrubber. Rinse thoroughly. This will help you tons.

    These Cats are giving you good info. Lots of smart cats on this site.

    You want quality bud... don't get lazy.. do the work. Spend time with them, but fight the compulsion to fuck with the res. You can over adjust. If it's within the acceptable range leave it alone. Also bear in mind some strains could prefer the PH a little out of the 5.8-6.3 range.. but it's pretty rare.

    And most importantly don't take anything any of us say too seriously. Good Luck.
  6. nxk - do yourself a favor and check out the hydro grow journals. You'll see that some hydro growers do change their water frequently, and some don't.

    NOT changing the water has nothing to do with being lazy. Some of us prefer to let beneficial bacteria build up in the system amongst other things ;)

    Best advice I can give you is to check things out for yourself, check out what other growers are doing and see if they'll work for you. Always check for a grow journal when someone is giving you advice. Plants speak for themselves :smoke:

    If you have questions when reading someone's journal, don't be shy. There are a lot of helpful, knowledgeable growers here at the City that are more than happy to help :cool:

    Good luck to you!
  7. Absolutely correct!!! I never change my water in clone/veg tubs until after the two . 5 months it takes them to get to move to flower. I also in the 65 days of flower don't change or should I say dump and clean the tub, why would I, I mean I asked this in another thread but as I said I have never done it and it has never been an issue. My ph in flower is around 5.2 to 5.7 and as a scientist/bontany expert wrote in a mag I read in veg the plants optimal uptake of N, which is best for vegging plants, is a bit higher that 5.8 more like 6.2 and in flower the optimal uptake of P/k is 5.2 in hydro... My rez is down almost a third every day so I top off with plain water every other day and water and renute next day back to the level of ppm I use.... Never have had a disease or issue so why would I throw out 55 gals of perfectly good organic Bonticare nutes???

  8. #8 the imitator, Aug 22, 2010
    Last edited by a moderator: Aug 22, 2010
    The style I use for changing the res is a bit different.

    I fill my res and do my nute mix and ph.

    I change my res every 7 days or when my res runs too low to keep recirculating through the pump.
    If my res runs low on day 5 woohoo!! I change out the whole thing.

    Most nutrient companies use PH buffers in their bottles to help stabalize phenShen you dilute an exisiting res with water the ph buffering agent gets diluted which can result to sporatic PH and nutrient deficiency problems, especially when adding additional nutrients to a rediluted res.

    I pour out after 7 days because in my opinion, the stuff that is left over in the res after that long is mainly a concentrate of salts and metals that weren't takin up by your girlfriend... By adding more nutrients and water to such a mix you only make a heavier concentrate of the bad stuff that isn't takin up, but you make the mix richer with new bacteria and water, now she's eating quicker with double the amount of salts and non beneficial elements.

    But like yoda said, you don't have to change your res weekly that's just what I feel is key :p

    happy day
  9. Exactly.
    If you don't change the res out regularly u run the risk of unstable chemistry.. better safe than sorry.
    Rep for being correct.
  10. Just a note... read some of the other threads about using Hydrogen Peroxide before deciding to put some in your reservoir. As someone told me, once you add it to the reservoir, it kills both the bad and beneficial bacteria. Before I knew to light-proof my reservoir, I was using it to protect my reservoir from algae. Then I stopped using it and I got root rot. I think this was because there maybe was benefical bacteria that protect the roots? And if so, they were aparently killed by the hydrogen peroxide. So I'm guessing that they weren't there to protect my roots which may have led to root rot for me.
  11. Thanks for the advice everyone [​IMG]

  12. So as have said I have never had an issue not changing. I have 28 plants under 1k hps on 6' mover, one t5x8 h/o flour side lighting, I get around 30 ounces in 65 days of flower in a 5'x6'7"x7' high area. Is that a good yield or should I reduce the number of plants for better if not.?

  13. thats not a bad yield for quick grow cycles. i will veg 2-3 week old clones and veg them for 10-14 days in my primary system and then induce flowering. 12 plants,2 gallon pots, 6'x5' area and i average anywhere from 24-32 ounces regularily of dry finished product.

    although 28 plants in that area isnt to bad if youre straight scrog'in. but if youre doing any prolonged lst ing id say thats to many.

    i try to change out my rez every 2 weeks, and top off in between. i check/adjust pH daily(if needed) i dont have to worry about any nasty buildup since i use a water chiller and keep water temps @ 65degrees. but the nutes can and do get used up, but as long as youre topping off with a nice complete nute - you should be fine
  14. How tall are yours when done? nutes you use? Ph in flower you keep? and strain and light? Thanks...

  15. Heres a new pic (today, day 12)


    Is the color fading normal? Im growing Caramelicious:


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