watering and feeding. are they the same?

Discussion in 'First Time Marijuana Growers' started by shawnyboy420, Sep 16, 2009.

  1. quick newbie question:

    wat is an appropiate feeding schedule? like how often are u sposed to feed plants the nutes compared to jus regular water? i kno to jus check the medium every so often up to 2 inches down to check for moister but once u start giving ya plants nutes are u sposed to give it to them in every watering? im on my first grow with aq rockwool medium aqnd everything is going ok but ive seen a lot of different advice and some has been useful i jus wanna see wat most poeple think. my grow is about 1 month old and is about 6 inches tall i been using maxi grow from general hydroponics as my food and a ph at about 5.7 the temp been a constant between 79 and 83. im using a 600w air cooled lamp. i been showing some yellowing on the top leaves that i kinda diagnosed as bleaching because i had the lamp s lil too close for about a day i raised the lamp and am waiting to see if theres any change. im on my first grow so any advice would really help thanks grasscity!
    oh yea get ur asses to hempfest in boston on sat the 19th!
  2. This is the Lucas formula and is meant for Hydroponic grows. I think that most will agree this is a great place to start for nute feeding.

    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 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.
  3. good info thanks man
  4. You can use hydro nutes in soil, but you should use less than half of what is recommended on the bottle to start out. You should be able to give 50% of what is recommended later on in the plants life. You can also cut your nutes even more, just water more often. Most commercial soil mixes have mixed in nutes and do not need anything added for generally as long as directed. You do have to take into account pot sizes, plant maturity and watering/nutrient needs, humidity levels, and I'm sure that list could go on. As far as feeding schedules, most major brands have websites and post ideal schedules, just follow those will a dilluted concentrate. The needs of your plants will change through your grow. :smoke:
  5. I am doing a soil grow. Most concentrates I have seen say 1/4 to half teaspoon every other watering. My soil seems to retain water so I only water once a week because of this. I use the nutes every watering, this has not caused any damage and the plants are doing well.
  6. You should be watering more often, at least a couple times a week. Your next time around you should add something to your soil for more drainage.

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