Lucas Formula

Im using 0-8-16 - For Flowering cycle (12/12) and my ppm meter is measuring about 700 ppm is it normal ?
Im using tap water and its about 80 ppm. My ppm meter is a cheap ebay one, so it might be the meter ...
 

roc Eazy

Member
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.

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.
this is good info; do i necessarily have to let my water sit for 3-4 days be changing my hydro resv. Do i need to let it sit for days and then add the nutes.. Or does it really matter... Time whole time thing? Thnx in advance
 

deezy305

Active Member
I've been using the lucas formula for almost a year now. I grow 2 different strains, white rhino and a bagseed Indica strain of unknown origin but KILLER pot. :-) During veg I use super thrive. When I move the plants to flower, I stop the super thrive and use epsom salt. That's it and that's all. And I can say this: My plants do VERY well. They stay a dark healthy green from beginning to end. The buds are big, well developed, with excellent trich production. I personally couldn't be happier with the results I've acheived with the Lucas Formula and the two additives I mentioned. It's nothing fancy, and actually quite simple, but very very effective. I doubt that I will change any thing I do. I'm quite happy with the results I get from using this simple method. Also, I love the low cost of only having to buy 2 bottles of nutes. Nutes can get so damn expensive...

I have 2 grow albums with lots of pics of my plants from beginning to end. Click on my avatar and check out my plants if you have any doubts as to how well the lucas formula can work...

Good luck to you all, and happy growing... I hope you have huge healthy plants yielding massive harvests, often!!! :-)

-S
so im planning to give the lucas a try. so should i just use micro and bloom? or micro and bloom w/other additives?
 

lowdime

Member
so im planning to give the lucas a try. so should i just use micro and bloom? or micro and bloom w/other additives?
Can I use additives with Lucas Formula?

You may. It is recommended that you do not introduce additives until your setup is dialed in. After you've ironed out any deficiencies and fully understand how your plant and strain likes to be fed, feel free to begin using additives (such as Floralicious) - not that the additives will help. For increased quality and yield, focus on good genetics, and ample light and temperature control, rather than trying to compensate for those with additives.
 
In theory, if my aero system has 36 sites I can do a perpetual grow with only one system because the nutes are always going to be around 1000-1400 weather it is a rooted clone or a plant that is finishing up its week 8 of flowering and there is no need for a flush. Is this info all correct?
 

drgreentm

Well-Known Member
In theory, if my aero system has 36 sites I can do a perpetual grow with only one system because the nutes are always going to be around 1000-1400 weather it is a rooted clone or a plant that is finishing up its week 8 of flowering and there is no need for a flush. Is this info all correct?
yes you could do a perpetual with this formula as it is the same throughout all of flower so you could introduce early flowering clones in as often as you want, i use the lucas formula but not in full just as a base guideline some of my strains will show deficiencies so i have to go a bit stronger than recommended.
 
yes you could do a perpetual with this formula as it is the same throughout all of flower so you could introduce early flowering clones in as often as you want, i use the lucas formula but not in full just as a base guideline some of my strains will show deficiencies so i have to go a bit stronger than recommended.
Thank you Drgreen, could you tell me more about the deficiencies you noticed so that I may have a heads up before/if it happens to me. I am growing Platinum Og Kush in Aeroponics.
 

drgreentm

Well-Known Member
so far i have ran white widow and bubba kush on this formula. the ww i had great results with and the bubbas where yellowing badly so i added some calmag and upped the micro to 10ml per gal and dropped the bloom to 15ml per gallon and it killed the problem leaves returned to very dark green and havent had a problem since, but again this so far is only with the bubbas the ww's run fine on the 8-16 formula so it just all depends on strain i guess.
 
so far i have ran white widow and bubba kush on this formula. the ww i had great results with and the bubbas where yellowing badly so i added some calmag and upped the micro to 10ml per gal and dropped the bloom to 15ml per gallon and it killed the problem leaves returned to very dark green and havent had a problem since, but again this so far is only with the bubbas the ww's run fine on the 8-16 formula so it just all depends on strain i guess.
Ok, I'm going to be running the FloraNova 8ml so if I see some yellowing I should add a lil calmag
 

hooked.on.ponics

Well-Known Member
Don't forget you can run the AN 3 part on the Lucas formula if you want to upgrade nutes.

And their new 3 part (Jungle Juice iirc) is supposed to be almost a clone of GH's, so it would work too I imagine.
 
I was undecided for my first grow on the nutes. This past week has been setup week. I'm going DWC, two 6 pot tubs and a res in a 4x4 tent.

I had already ph'd my RO water when after purchasing GH micro & bloom I read I dont need to ph adjust.

My seeds are presently germing and will be planted tomorrow. I will do a complete res/water change in 7-10 days.

If I add 1/4 nutes now, 12-6 hrs before planting seeds, should I expect to need to PH down before the plant? There will be a constant drizzle of aerated water on the rock wool.
 

karmeron

Active Member
You would need to check the PH with a meter every few days. In my experience with those nutes you do need to adjust every now and then, also the more nutes you use (to a point) the less adjustments need to be made, so if your using 1/4 strength you will probably need to adjust. To be on the safe side check it with a ph meter.
 

hooked.on.ponics

Well-Known Member
I had already ph'd my RO water when after purchasing GH micro & bloom I read I dont need to ph adjust.
You do have to adjust pH with General Hydroponics. It's the new Advanced Nutrients that doesn't have to be adjusted.

If I add 1/4 nutes now, 12-6 hrs before planting seeds, should I expect to need to PH down before the plant? There will be a constant drizzle of aerated water on the rock wool.
If you're just germinating the seeds you don't want to feed them. Wait until the first true leaves appear before you start giving them nutes. Until that time they're running off stored energy from the seed and giving them nutes will burn the hell out of them.
 

boodadood

Active Member
has anyone experienced weird bud smell and taste after using GH LF? ive used it twice now in hydro and a buddy of mine has used it a few times with coco and we keep getting the same aftertaste/smell...its like a stinky whore's locker at the ymca in harlem smell...anyone? flushed them shits for 2 weeks...anyway, i just made the switch over to technaflora recipe for success...we'll see what happens
 
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