i need a new recipe for GH floro 3 part or better. I've used GH floro forever but now i keep getting Mg deficiency. I have to add tons of cal mag and or epsom salt but still get a symptoms of Mg deficiency. i also think that thep ppm with additives may be different. i don't know. I want to use cocoa/perlite mix. I've been trying to calculate levels but figure someone out there has a proven recipe that will deal with this mg deficiency. i use RO water.
What you need my friend is the
Lucas Formula. The Lucas formula eliminates many problems, including Cal/Mag deficiencies.
The
lucas formula eliminates the need for the grow part of the three part formula and only uses the Micro and Bloom parts.
The formula is simple:
1 part micro
2 parts bloom
I only use it during bloom, very simple. Keep PPM roughly 1300 from beginning to end of flowering (except flush last week) at a ratio of 0-1-2 or 0 grow: 1 micro: 2 bloom. My PPM fluxuates between 1150 and 1400 but I try to average about 1300. I have a simple addback formula, adding back at half strength when I top off.
Here are the formal instructions for using the Lucas Formula from a post by
sealfever42.
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)
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.
https://www.rollitup.org/hydroponics-aeroponics/4387-lucas-formula.html
This should be what you need!
-GTS
if so what nutes out of what i have would you use, i am about a week and a half into flowering. i have a 5 gallon bucket setup with 2 airstones and keep the res about 3 1/2 gallons full.kiss-ass
