1st time ebb and flow tables

Discussion in 'Hydroponic Growing' started by 9990s, Dec 7, 2011.

  1. So I understand the general basics on this setup but lack details. I'm using the big 5" rockwool cubes and 4' x 4' trays So my questions are; how deep do u flood tables? How quick do u drain it? And do u leave any standing water in tables after draining?
     
  2. I have never used tables, only buckets, but the concept is the same. I flood my buckets to within 2 inches of the top but I have 3 buckets that are an 1.5" lower then the others so they fill almost right to the top. I do not notice a difference. So I would fill your table right up and then 15 min. later drain it. You want to drain as much standing water as possible. You will have enough water absorbed into your medium to keep your plants feed and watered. Do you have hydro-tons or rocks in your tray around your cubes?

    With my buckets I want to get the water out of the buckets as fast and as completely as possible. If I still have any water in the bottom of my buckets and in the tubing, the roots will follow this water and clog the tubing. Then I can have a bucket not getting enough water. I don't know if you have to worry about any of this with your setup
     

  3. ...I use flood tables myself.....here's a link for you to follow that has a calculator to figure your irrigation frequencies. --> Cannastats - Ebb/Flow Tips
     
  4. I'M GOING 2 USE A COCONUT ROOT MAT 4 THE BOTTOM OF THE TRAY AND THE ROCKWOOL BLOCKS THEMSELVES R QUITE LARGE. GRODAN CUBES LIKE 5"-6". BEEFY ENOUGH TO SUPPORT SINGLE ST:smoke:OCK COLAS 18"-36".:smoke:
     
  5. For big blocks and coco mat I would flood for short amount of time. Don't need to flood too high, just until the cube gets soaked. Don't flood again until blocks start to dry out but not completely. Really easy to over water flooding big cubes cause they hold water more then hydroton. Feel the weight of a dry cube vs. wet & only flood when they feel light again.

    Basically watch them like a hawk until u get a feel for how often to flood. Your water pump big? The duration to turn on will be longer if your pump is small and can't deliver the solution rapidly.

    Try 5-10min on. 2-4hr off. Watch them every 30min to see how wet they are. Only flood when blocks start to dry
     
  6. Hey,
    I am just about to start grassomatic maxigom. 1000 hps watt system using an ebb and flow table, rockwool and hydroton as my media. I haven't done a grow for a few years and things have changed! I am in the market for nutes and want to know if anyone has any advice on a feeding schedule and could recomend a good nutrient recipe. I have the table and the res but I am not totaly sure if I want to be using this media for my first auto grow. The seeds are here but I realy want all my ducks in a row befor I embark on this wild 75 day ride. any input would help.
     
  7. #7 trichome fiend, Dec 16, 2011
    Last edited by a moderator: Dec 16, 2011
    ...you can click onto, "my minifarm" linked in my sig to see the results.
    - Lucas Formula-
    General Hydroponics Flora Series Feeding Strategy

    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)

    Example:

    ((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 Hard Water GH Micro

    I had been experimenting with using the Hard water Micro as a substitute for the normal Flora Micro, this to account for my hard 350 PPM water and the lack of a large enough RO filter at the time. It has worked well for me. I just kept my reservoir below 1150 PPM @ .5 conversion and its all good.

    One tip - do not pH down this stuff, the hard water micro will drop pH gradually over the next 24 hours, for example I mix up a batch, it is at like 6.2, the next day, its at 5.6-5.8 after running in the system for a while. If I pH downed that to 5.7 before putting it in the system, it ended up as low as 4.8-5.2 by the next day.

    My conclusion, the hard water micro was buffering the alkaline crud in my water, it just doesnot do it ASAP fast like the phosphoric acid.
     

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