PH Buffers

Discussion in 'Hydroponic Growing' started by Intrepid One, May 28, 2010.

  1. Hey guys i have a question regarding PH buffers. What can be used as a buffering agent in your reservoir ?.

    I have kept fish for years and i know that a person i able to buffer their aquariums by adding crushed coral to their reservoirs, helps to stabalize the PH.

    So knowing this is their anything that can be used in a hydroponics reservoir to try to buffer the PH to a stable level ?

    I am new to this whole growing thing and i am having trouble keeping my PH at a stable level. When i mixed up my 3 part and checked i was at 6.3 if i add 1.5 ml of PH down it will drop to 5.7 or so and then return to something like 6.2

    I have been trying to reach 5.9 and have it stay there but it seems almost impossible unless you were to add PH down a couple of times a day

    I look forward to any thoughts or suggestions on this thanx for your time
  2. What type of system are you using? First thing that comes to mind is that it sounds like you're using hydroton pebbles and didn't soak 'em in pH corrected water before using, happened to me once before.
  3. Yes your assumption is correct i am using hydroton pebbles (lil brown round balls) and no they were not soaked in PH corrected water prior to use. We did give them a good rinse before we started but it was just in ordinary tap water which our tap water is right around a PH of 6.8.

    So basically what i am screwed now ? i don't think i would be bale to get the plants out of the hydroton to soak em now.

    This is my first attempt at growing, and what a learning curve it is. have my plants with their 4th set of leaves
    PH 6.3
    nutes 1010
    temp 74f
    25 liters of Nutes in the resrvoir
    400 watt MH 18/6
    6 buckets with pots in the lids
    airstone in each bucket / 1 in the reservoir

    From that i understand i am trying to achieve a PH of 5.5 - 6.1 correct ?

  4. That's probs cool, always kept mine at 6.2/3 at mix and expect a drop with retic or flood/drain...Autopots...set and forget...and no flushing...
  5. I would dump the reservoir then run a gallon or 2 of pH corrected (5.8) water over the hydroton in each bucket, get rid of all the old water, then refill the reservoir.

    The temp looks good, lights are good.

    Nute ppm looks mighty high for a new plant, for veg I recommend almost half that value (using a 0.5 meter).

    What light(s) are you gonna be using for flowering?
  6. I am planning on purchasing either a 600 watt HPS or a 1000 watt HPS haven't really decided that yet, figure i still have approx 6 weeks to sort it out but is all gonna depend on the temp in the room.

    I am using general hydroponics 3 part solution , Flora Micro, Flora Grow, flora Bloom.
    i was under the understanding from their website that young plants were on a 1010 nutrient level until later in the stage and they go to a 1080 mix.
    I could have jumped the gun and started them on too high of a dose.i will re-check their site and go with the value for seedlings

    i guess i have a rain day today from work so i will mix up some water with a PH level of 5.8 empty my reservoir and buckets and flush out the plants/pots and mix up a new batch of nutrients and see if that helps to stabilize the PH levels.

    I am using a Nutradip Tri-Meter that reads PH,Nutrients and Temp
  7. Since you're already using GH nutes, you might wanna try the Lucas Formula. It's simple to use and almost fool-proof :)

    General Hydroponics Flora Series Feeding Strategy - Lucas Formula

    G-M-B (Grow-Micro-Bloom)
    0-5-10 - For Vegetative cycle (18/6)
    0-8-16 - For Flowering cycle (12/12)

    The numbers above indicate the number of milliliters (ml) of Flora Grow, Micro or Bloom formulas that I use in one gallon (US Liquid) of nutrients.

    You will notice I dont use any of the Flora “Grow” formula, do not need to, the Flora "Micro" provides plenty of Nitrogen.

    There are two ways to work with this formula:

    1. Top off the reservoir daily using a pH corrected water solution as required to maintain full reservoir level. After adding back an amount of water equal to the amount of your reservoir capacity you should change the reservoir and put in fresh solution.

    2. Top off the reservoir daily using a pH corrected 100% strength nutrient solution as required to maintain full reservoir level. Continue to use this nutrient solution without dumping the tank unless the PPM rises above acceptable levels.

    Between vegetative and flowering cycles you should dump your nutrients, then flush (possibly with Clearex) to remove salt buildups, then change to the other feeding program. Always shake your GH nutrient bottles before using them!

    For young plants, just transplanted into the hydro setup, give them 50% strength nutrient mix to prevent overfeeding them while their young. Gradually bring up the mix to full strength as they grow over the next few weeks or so.

    The lucas formula is normally intended for use with RO or near 0 PPM water.

    NOTE: The Lucas formula eliminates the need for Epsom salts to correct (Magnesium) Mg deficiencies in most normal feeding programs recommended by manufacturers. Cannabis needs a lot of Magnesium to thrive.

    The Flora Micro is providing the Nitrogen and the Magnesium in the proper balance, thus there is no need for the Grow formula and little or no room under the maximum acceptable ppm limit of 1600 @ 0.7 conversion.

    Calculated EC/TDS levels:

    EC microsiemen:
    0-4-8: 946 µS
    0-5-10: 1184 µS
    0-8-16: 1894 µS

    TDS @ 0.5 conversion:
    0-4-8 = 473 ppm
    0-5-10 = 592 ppm
    0-8-16 = 947 ppm

    TDS @ 0.7 conversion:
    0-4-8 = 663 ppm
    0-5-10 = 829 ppm
    0-8-16 = 1326 ppm

    Addback Calculator - (For Advanced Users)

    Say you were running the 0-8-16 formula, at 0.7 conversion with a 22 gallon res. When you first fill it up, your ppm will be around 1330.

    Now you have been growing for a week, and some of the water has been taken up by the plants, some has evaporated, and now your res is at 947 ppm. You need to get your ppm from 947 to 1330. Here is the equation:

    ((target - current) / target) * 8 ml per gallon * res gallons = Flora Micro (ml) double this figure to get Flora Bloom (ml)


    ((1330 - 947) / 1330) * 8 * 22
    (383 / 1330) * 8 * 22
    0.3 * 8 * 22 = 53 ml Flora Micro

    53 ml Flora Micro, double that and you get 106 ml Flora Bloom. So 53 ml Flora Micro and 106 ml Flora Bloom to add back to your 22 gallon res to get you from 947 to 1330.

    Using GH Flora 3-part liquid nutes:
    0ml of Grow, 8ml of Micro & 16ml of Bloom per gallon of RO.

    Lucas Method(s)
    The method you use to maintain the nutrient levels in the reservoir, after you've mixed them, depends on the equipment you have & your level of understanding. There's a simple change-out method & an add-back method. Both are very successful with the add-back having a higher yield but also being a bit more complicated & requiring an EC/TDS/PPM meter of some sort. I highly recommend anyone new to the community to use the simple change-out first & to only use pH drops or a pen for it. It will allow you to concentrate on the plant more.

    Simple Change-out method
    This simple method for using the Lucas formula only needs pH drops or a pH pen to be successful with. Let's use a reservoir that holds 10 gallons of mixed nutrient solution as our example.

    [FONT=&quot]Using GH 3-part: 10 Gal

    Add 80ml of Micro & mix it in well.
    Add 160ml of Bloom & mix it in well.
    Adjust pH to 5.2

    Mark the level of the nutrients in your reservoir. Keep the level of the reservoir the same by adding RO water & keep track of how many gallons you're adding.
    Once you've added back the original number of gallons you mixed (in our case, 10 gallons) it's time to dump the reservoir & mix a fresh batch of nutes.

    That's it! (wasn't that simple? )

    You'll notice that I didn't mention adjusting the pH again. That's because you won't have to. All you should do on your first grow is check the pH daily & mark it down. Keep track & see the pH swing as it goes up & down through the life of the res. Watch the plant too & write down any changes you see in growth. If your pH bottoms out below 4 you have root rot or some other issue, adjusting your pH won't help.

    !!!!!!Note On 400w HPS & Lower Power Lighting: You May Find That Your Plants Don't Have Quite Enough Light To Grow Properly In A Full Strength Solution. Start With 0-5-10. Increase To 0-6-12 If Your Ph Steadily Rises & Goes Above 6.1. Keep Adjusting The Strength Until Your PH Swings Between 5.2 & 6.1 Without Going Past Those Points. Make Sure You Write Everything Down So That Once You Figure Out What Your Plants Like For Your Situation You Can Mix That Strength To Start With The Next Time.
    Just Remember That If Your PH Goes Up Out Of Range Over Time & Doesn't Come Back Down, You're Not Feeding Enough. If Your PH Slowly Goes Down & Down Below 5.1, You're Feeding Them Too Much. (This Is Of Course Assuming That Everything Else In The Garden Is Good.)!!!!!!

    This Is Not Mine

  8. #8 BadAxe, May 28, 2010
    Last edited by a moderator: May 28, 2010

    Hey listen. Have u considered using the Lucas Formula sine you are using GH Flora? (Seems like I am relate to Lucas I talk about him all the time, lol) But here is why I suggest it.

    I am currently using the Lucas formula. I am also using Hydroton that I only rinsed very well with tap water, no soaking. I am using a DWC setup in an 18 gal res. I have zero PH issues at all. And I got some hard tap water. I am using RO water in the res, just used the tap water to rinse the rocks.

    Your ppm is perfect where it is unless your plants are suffering. I started with 50% nutes, and my WW did ok, and my Northern Lights hated it. As soon as I switched to full strength nutes (1060 ppm) they exploded.

    I am also doing zero flushes for my entire grow using the addback with nutes formula. Everyday I take readings, and everyday my numbers are spot on, and my plants are looking very happy.

    So I would look to the Lucas form since you are already using the nutrients that you do with the LF. It truly is simple and helps keep all your numbers in line right from the start, and gives you much less worry. Don't lower your ppm though. Especially if the number is staying steady from day to day, that means your plants are eating nutes and drinking water equally. You will only need to change it if you see your numbers varying greatly when taking readings. If the number goes a lot higher, they are only drinking the water, if they go lower, they are eating more than drinking.

    Anyway, consider giving the LF a shot, you may just love it, and it may solve your PH problems. But really, don't panic like your screwed. Your not. I did the same thing that you did, and I am doing just fine.

    Here is my WW and NL at day 17. The NL is recovering from major growth stunt due to the 50% nutes. She is recovering now but has some catch up to do wit the WW, that liked the 50% but LOVES the 100%. Good Luck.

    Attached Files:

    • WW4.jpg
      File size:
      87.7 KB
    • NL3.jpg
      File size:
      75.3 KB
  9. initially our PH numbers were through the roof. soon as we did our mix and added it to the reservoir it went from 7 to 8 then we were manually adjusting it with vinegar until the next day when we were able to get to a store and get some PH down.

    we got it down to a somewhat stable 6.3 but i am having to add 1mil a day or so.

    my nutrient levels are holding steady at 1010 , when i mixed up initially they were around 760 or so and we were slowly adding grow to the reservoir until it reached 1010 and has been steady as a rock there.

    i am growing bag seed at the moment to try to learn this and then i plan on spending some coin on some seeds, but i figured for now i could kill some misc plants and not feel too bad about it , that being said out of the 6 plants i have growing 2 of them seem to really like it in there , 2 so so , and 2 of them have just a touch of curling on a leaf or two.
  10. well for fun this evening i pulled all my baskets and put them in a solution of water with a PH of 5.8 for approx 10 mins emptied the reservoir and changed my nutes to the lucas mix

    ph adjusted my water to 5.8 before adding to my reservoir and have had to add another mil and a half and to drop it back from 6.2 to 5.8

    so what i have now are :

    PH 5.8-6.1
    Nutrients 850
    temp 78f

    have to see now if it stabilizes any now that we have done all this

    thanks for the input guys, i am thankful for the helpful input.

    The learning curve is STEEP ! lol
  11. ppm seems a little low for the Lucas Formula. Depending on the conversion factor of your meter, when you use the Lucas Formula of (0-8-16) your ppm should be around 1000 with the .5 conversion and 1300-1400 with the .7 conversion meters.

    Unless you are growing under flouro's in which case the Lucas Formula is 0-5-10 in which case your ppm numbers are right on.
  12. no i am growing under a 400w MH , i do have 4 4' fluro's 1 in each corner just for supplemental lighting.

    I don't quite get the .5 or .7 conversion you are talking about thou. could you elaborate a bit on that for me to get it clear in my simple mind thanks
  13. i have even pulled out the manual for the tri meter , all i see in there is :
    Nutradip Tri-Meter Model 202 PH,EC,Temp
    range : 0-9999 ppm / temp 40 -90 f
    accuracy : +/- 2%
    Resolution 1ppm
    calibration : 1 point manual

    and i have bought the calibration solution and calibrated the meter with 1000 ppm solution, as well we did the ph meter with a solution of PH 7
  14. Don't know if this helps to elaborate any on what we have done this is what we mixed

    Water : 46 liters
    Flora Micro :60 ml
    flora bloom :120ml

    we also added 2.5 ml of ph down to get it to 5.8

    a few hours later it was at 6.2 where i added an additional 1.5 ml Ph down

    my meter was displaying 840 -850 last night when i looked.

    the meter is mounter to the wall above the reservoir and is constantly reading the reservoir, it is that style of meter

    hope this helps and thank you for taking the time to help me out
  15. #15 K.O.G., May 30, 2010
    Last edited by a moderator: May 30, 2010
    If your tri-meter is the model 202 it reads tds at a .5 conversion. That's the one i have also. good to see you switched using the lucas system. it's fail proof. Everything else sounds great!
  16. It does sound like the hydroton could be the source of your problem, but PH flucuation is just in the nature of hydro. Wait until you get to late flowering, when your plants are eating up nutrients fast as ever, you PH WILL flucuate even if everything else is done perfectly.

    and here's a suggestion for your next grow.. don't use hydroton. use hygromite, its much much better. I can't beleive more people don't use it, I will only be using hygromite from now on. Hygromite, like hydroton, is little pieces of light "rock" but unlike hydroton it's light gray in color and irregular shaped. Hygromite is PH neutral, and add's silica to your grow. Silica strengthens cell walls, which makes plants stronger and more able to handle stressfull conditions, like irregular light cycles, hot/cold temps, insects, etc.

    anyways... good luck to you

  17. That is not necessarily true. If you get your hydro system dialed in, and find the level that the plants eat equal part nutes and water, your numbers will remain constant. You will have little fluctuations with PH, but nothing drastic. Its when people start using 6, 7 , 8 different nutes and additives that things start to fall apart. (When they don't know what they are doing with all of those nutes). But stay on par with the right amount of nutes for their intake, and your PH will remain steady.
  18. What i noticed after changing formulas was that the leaves started to shrivel up and didn't have quite the same look to them.the nutrient's were steadily rising from where we were at 850 to 900 while the PH seems to have settled down and is more easily adjustable.

    i took 10 liters out of the reservoir and replaced it with PH adjusted 5.8 water which in turn dropped the nutrient levels to the 750 ppm range and i have the pH staying approx 5.9 or it has most of the afternoon.

    have to see how it goes i guess
  19. i also see on the outside of the box that the TDS meter is .5% conversion so now it is starting to make sense. i see that i have had the nutrients high for the last lil bit and it also explains the appearance of the plants, they look a bit nutrient burned.

    So the PH level looks like it has settled out to 6.0 and is staying there.
  20. Sound like you got it handled bro!

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