Full Version: Lucas Formula
hi there does any one know the mix per litre of flora micro/bloom,just ordered these nutes no reverse osmosis though, cheers
Where did that come from? Looks like a variation for coco as it's using 2 micro to 3 bloom mostly. Thanks for posting it though, I'd heard there was a lucas formula mix for coco developed and that might be it, will give it a go when I try coco.
lucas himself never flushes and it's one mix feeds all apart from newly rooted clones. 8ml micro and 16ml bloom per US gallon is the standard mix, aka 0/8/16. (The zero is the grow of GH 3 part, never used.) For convenience, that was rounded up from the original 0/7.5/15 but using 0/2/4 per litre makes it a tad closer to the original.
From the day the seeds sprout to the day before harvest, that's what they get with no additives or supplements. Young clones get 0/5/10 per US gallon which is 0/1.25/2.5 per litre.
For tap water, use 5% to 10% more water so a 20 litre batch would start with 21 to 22 litres of water, add 40ml of micro then 80ml of bloom. Give it a stir and measure the pH, adjusting as necessary. Never let the micro and bloom mix undiluted. I have separate measuring syringes for each bottle. Different sizes to avoid stoner errors and I've cut a line for the 40ml on one and 80ml on the other so that I don't need to replace them when the markings wear off.
I've been doing it that way for many years now, it really does have everything the plants need.
lucas himself never flushes and it's one mix feeds all apart from newly rooted clones. 8ml micro and 16ml bloom per US gallon is the standard mix, aka 0/8/16. (The zero is the grow of GH 3 part, never used.) For convenience, that was rounded up from the original 0/7.5/15 but using 0/2/4 per litre makes it a tad closer to the original.
From the day the seeds sprout to the day before harvest, that's what they get with no additives or supplements. Young clones get 0/5/10 per US gallon which is 0/1.25/2.5 per litre.
For tap water, use 5% to 10% more water so a 20 litre batch would start with 21 to 22 litres of water, add 40ml of micro then 80ml of bloom. Give it a stir and measure the pH, adjusting as necessary. Never let the micro and bloom mix undiluted. I have separate measuring syringes for each bottle. Different sizes to avoid stoner errors and I've cut a line for the 40ml on one and 80ml on the other so that I don't need to replace them when the markings wear off.
I've been doing it that way for many years now, it really does have everything the plants need.
QUOTE (lazi @ Oct 25 2009, 11:57 AM) 
Where did that come from? Looks like a variation for coco as it's using 2 micro to 3 bloom mostly. Thanks for posting it though, I'd heard there was a lucas formula mix for coco developed and that might be it, will give it a go when I try coco.
I knocked it together with the info from Lucas' original post on icrag I think, about a year ago. I don't remember making any coco-specific changes to it, but my memory ain't what it should be
I've never run it though. Started using GH 3 part doing F&D and failed miserably, went to coco and never looked back so I've never had the chance to use those bottles (actually, that means that those tables are most likely not for coco and for hydro).
GN
General Hydroponics Flora Series Feeding Strategy - Lucas Formula THIS IS FOR US GALLONS SO NEEDS CONVERTING TO L. 1 us GALL = 3.785412L
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. (RO = Revers osmosis, you can get a 3 stage unit for 50 quid)
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.
Regards cain1.
PS Just copied off another site, I aint used it yet, but will be in the next day or so when my Nurients arrive. So the stuff about hard water etc.. is what Lucas has said.
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. (RO = Revers osmosis, you can get a 3 stage unit for 50 quid)
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.
Regards cain1.
PS Just copied off another site, I aint used it yet, but will be in the next day or so when my Nurients arrive. So the stuff about hard water etc.. is what Lucas has said.
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