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Can someone explain this LUCAS so called FORMULA to me...

Hydro-Soil

Active member
Veteran
I hope my plants don't see 10k's posts.
They don't know that they shouldn't be doing so great.
Please nobody tell them.:D
After all the great things I've seen coming out of you 10K, that last post was kinda weird for me.

Adding nutes to the res is only dangerous if you have bare roots hanging in it. Mixing in additional micro and then bloom or a bit more FloraNova doesn't hurt a damn thing. Now, I can't say the same for other nutes.

The rest of what you're talking about applies to other nutes but not the Lucas formula, as far as plants eating certain things and leaving an imbalance. Lucas and many others have done add-backs and run 2-3 crops before changing the res with awesome results. Personally I'll stick to a single crop cycle. :D
 

10k

burnt out og'er
Veteran
Dongle69 wrote...
I hope my plants don't see 10k's posts.
They don't know that they shouldn't be doing so great.
Please nobody tell them.

The beauty of the Lucas formula is that it is already a properly balanced "diet."
It is so simple that some make it sound complicated.
I am constantly experimenting myself, but Lucas formula has always worked for me.

Remember folks, it is O.K. that people do things different from you, and you can do things different than them.
If my plants are happy, I'm happy

I believe I was speaking to Turbolaser4528, but anyway...
Like I said earlier in this thread, it would go "right over some folks heads"
Just how much of my post did you even bother to question or even comprehend ?

Maybe I can explain it in a way you could understand better. It's about proper mixing, pHing and res maintenance.
Done incorrectly can cause some damage to the chem hydro nute solution and your plants.
You would rather ridicule me than ask some questions. Research may be necessary in your case.

Hydro-Soil wrote...
After all the great things I've seen coming out of you 10K, that last post was kinda weird for me.

Adding nutes to the res is only dangerous if you have bare roots hanging in it. Mixing in additional micro and then bloom or a bit more FloraNova doesn't hurt a damn thing. Now, I can't say the same for other nutes.

The rest of what you're talking about applies to other nutes but not the Lucas formula, as far as plants eating certain things and leaving an imbalance. Lucas and many others have done add-backs and run 2-3 crops before changing the res with awesome results. Personally I'll stick to a single crop cycle

Hydro soil, you may have never worked with pure chem hydro mineral salt nutes like GH flora series, so maybe you've never seen or heard of elements precipitating within the solution and becoming unavailable. And instead of discussion you choose to ridicule me instead of asking questions..and you're writing lucas mix instruction threads here on icmag telling people not to pH their mixed hydro nute solutions ?

"doesn't hurt a damn thing" you say ?

If that's the way it's going to be, then I'll just wait for more ridicule, let the folks pile it on some more before I show you a few quotes from the experts, colleges, magazines etc. to back up what I'm saying.
 
D

dongle69

10k, I eagerly await your thread.
Throw some pics up of your plants while you are at it.:ying:

It would do you well to lighten up a bit, eh?
 

Hydro-Soil

Active member
Veteran
Hydro soil, you may have never worked with pure chem hydro mineral salt nutes like GH flora series
Only for a few years, but go on....

so maybe you've never seen or heard of elements precipitating within the solution and becoming unavailable.
Seen? No. Heard? Yes.

And instead of discussion you choose to ridicule me instead of asking questions..
Frankly I was a bit shocked and am a little out of it due to being sick. Sorry.

and you're writing lucas mix instruction threads here on icmag telling people not to pH their mixed hydro nute solutions ?
I never said anything of the sort. I did state that I've never added pH'd RO water to any of my reservoirs, ever. Unless your numbers are bang on after mixing(I've yet to see that myself), nearly everyone needs to pH their solutions.


If that's the way it's going to be, then I'll just wait for more ridicule, let the folks pile it on some more before I show you a few quotes from the experts, colleges, magazines etc. to back up what I'm saying.
Just going on experience with the Lucas formula. Lots of quotes and experts and colleges and magazines haven't ever used the Lucas formula. It's pretty dang well balanced and doesn't have all the other issues you spoke of.

That was the entire reason Lucas spent all those years pimping it on the net. Silly! :D
 

turbolaser4528

Active member
Veteran
i love you guys, you make my night. fucking comical hahah but genius!!!!!!!!!

10k you're a funny dude, I also eagerly await your thread on the proper techniques of hydroponic reservoir management (or whatever you wanna call it)

I almost died like 7 times riding home from this bar on my bike tonight, makes you appreciate life. Actually no it didn't i still like living though, its interesting,







?NUTE WRITE UP YES HORRRAAHHH!!!!! stay safe, grow the green, never give up your dreams:2cents:
 

10k

burnt out og'er
Veteran
Just going on experience with the Lucas formula. Lots of quotes and experts and colleges and magazines haven't ever used the Lucas formula. It's pretty dang well balanced and doesn't have all the other issues you spoke of.

That was the entire reason Lucas spent all those years pimping it on the net. Silly!

I didn't say the lucas formula was poorly a balanced diet..."you silly numbskull !"

On the contrary, it's a fine gh ratio. But as a hydro chem purist, you need to understand that ALL chem salts mineral nutrient packages, including the lucas mix and all the other gh flora series multi-part mixes are subject to mishandling, much more than most people realise.

My aim is to point out how to NOT end up with a damaged solution in the reservoirs from improper handling, mixing and maintenance. This is a topic that has been written about in countless hydroponics magazines and college studies, but it just goes "right over some folks heads". I've even written faqs on it a decade ago and had this discussion wayyy too many times.

I'd go into it further if folks care to know, but it's basically don't add the concentrates to already mixed solutions without first diluting them in straight water first, same for adding pHing chems, additives and various snake oils, don't add them in concentrated form. Solution damage, although ever so slight does have a cumulative effect on what precipitates and becomes unavailable over the long term, which is another good reason to change out the res once in a while. The practice of keeping one res going long term multiplies that problem, not to mention the balance within the solutions becoming damaged or "altered" in time by not replacing the reservoir solution on a regular basis with a fresh mix.

There are better ways to accomplish the top offs, by properly premixing an add back nute solution, and using that for reservoir maintenance top offs Sheeeesh !

Here we go with another metaphor. Do you change the motor oil and filter, or would you rather just keep that old filter and oil for a couple years. pfeeeeew

I was only attempting to point out that:
There is such a thing as managing nutrients by mass balance !
There is such a thing as elements precipitating in solution from poor maintenance, mixing, pHing, add backs techniques causing badly "damaged" reservoir solutions, and the evidence is in the infirmary on an almost daily basis !

But instead I get flippant show your pictures, insults and wise cracks.
Well pHuck that! I've spent over a decade showing pictures and what not at Overgrow and I don't feel that I have to prove a damn thing with further incrimination on the internet. That ended when Overgrow ended and that's all I'm going to say about my not having a gallery here at icmag. I wasn't born yesterday and I'm not here in this capacity just for shits and giggles!

Dongle, you edited out one wisecrack remark asking me what the pH is of chocolate cake is ?

Well here's you damn chocolate cake Dongle69...
Only Dr Bruce Bugbee, director of the Utah State University Plant Physiology Lab used dog food for his motaphor about nute solution maintenance, mass balance.

MANAGING NUTRIENTS BY MASS BALANCE During the past 12 years, we have managed nutrients in closed hydroponic systems according to the principle of "mass balance," which means that the mass of nutrients is either in solution or in the plants. We add nutrients to the solution depending on what we want the plant to take up.

Plants quickly remove their daily supply of some nutrients while other nutrients accumulate. This means that the concentrations of nitrogen, phosphorous, and potassium can be at low levels in the solution (0.1 mM or a few ppm) because these nutrients are in the plant, where we want them. Maintaining a high concentrations of nutrients in the solution can result in excessive uptake that can lead to nutrient imbalances.

For example, the water removed from solution through transpiration must be replaced and it is necessary to have about 0.5 mM phosphorous in the refill solution. If the refill solution was added once each day, the phosphorous would be absorbed by the plant in a few hours and the solution phosphorous concentration would be close to zero. This does not indicate a deficiency, rather it indicates a healthy plant with rapid nutrient uptake. If the phosphorous level is maintained at 0.5 mM in the recirculating solution, the phosphorous concentration in the plant can increase to 1% of the dry mass, which is 3 times higher than the optimum in most plants. This high phosphorous level can induce iron and zinc deficiency (Chaney and Coulombe, 1982).

Feeding plants in this way is like the daily feeding of a pet dog, some dogs would be far overweight if their food bowls were kept continuously full.

Here's a few quotes from General Hydroponics regarding nutrient def's and tox's from poor mixing, maintenance, water quality etc...
Water quality (from General Hydroponics)
The quality of the water that plants receive will affect their health and vitality. Municipal water
can contain harmful additives, such as chlorine, and even natural well water can contain an excess of minerals or have an extreme pH. A surplus of many common elements in water can cause a chain reaction in a nutrient solution, resulting in many of the vital elements fusing together and becoming unavailable to the plants

pH and nutrient availability (from General Hydroponics)
The pH of a nutrient solution describes its acidity or alkalinity. Although extremes of pH
can damage roots, the primary reason that pH is relevant to growers is that it affects whether
certain elements in the solution are available to the plant or not. Specific nutrient deficiencies
can arise in a well balanced nutrient solution if that solution exceeds the optimum pH range.
Therefore, it is beneficial to your plants to monitor and adjust pH as needed to ensure
complete nutrient availability. Many factors work to change the pH of your nutrient, including
microbial activity, atmospheric interactions and recirculation.

Specific nutrient deficiencies (from General Hydroponics)
Hydroponic nutrients contain all elements needed by plants. Under normal circumstances,
all elements should be available and nutrient deficiencies will not occur. A pH imbalance can
cause nutrient deficiencies by creating mineral interactions. Hard water or incorrectly mixing
nutrients directly together will also contribute to pH problems. If you observe signs of a specific
nutrient deficiency while using high-quality nutrients, examine environmental factors first.

Here's a hit from Maximum Yield magazine...
The significance of pH 5.0 to 6.0 (Excerpted from an article in Maximum Yield magazine, Flairform)
It is over this pH range that all growth factors produce optimal growth. If the pH is allowed to rise much above 6.0, more than half the essential nutrient species (especially calcium, sulfate, and the trace elements copper, iron, manganese, and zinc) can precipitate, thus becoming immobile and unavailable for transport by the water flow to the roots. The precise pH at which precipitation of macronutrients starts is determined by the combined concentrations of calcium and sulfate. Except for fertilizers low in calcium and sulfate, this problem commonly occurs at pH values of around 6.5 for concentrations that would yield conductivities of 2.5 mS/cm in distilled water and pH 7.0 for 1.5 mS/cm. Hence, to avoid
precipitation, higher nutrient concentrations generally must be held at lower pH values.

In spite of this precipitation problem, some references advocate pH values well above 6.5 for some plant varieties — a condition that risks depleted concentrations of the above-mentioned elements. This is incorrectly justified by quoting the chart in Figure 4 as proof. As highlighted, it is important to realize that these data are based on soil culture.
It is about Hydroponics & chem nutes, not about soil culture /|\

hth,
10k
 
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10k

burnt out og'er
Veteran
ps...
The rest of what you're talking about applies to other nutes but not the Lucas formula, as far as plants eating certain things and leaving an imbalance. Lucas and many others have done add-backs and run 2-3 crops before changing the res with awesome results

:laughing: :laughing: :laughing: :laughing:

Funny stuff Hydro-Soil they ran two or three crops without changing the reservoir with awsome results... :yoinks:
heh heh heh... "Awesome results..."Bullshit" silly silly bullshit !

:Bolt:
 

Hydro-Soil

Active member
Veteran
I didn't say the lucas formula was poorly a balanced diet..."you silly numbskull !"

:yoinks:

I'm hoping you're ok 10k and yes, I'd love to see your write up because all that stuff after the quote above applies to general res maintenance. Isn't that supposed to be a given when discussing nutrient formulas?
 

10k

burnt out og'er
Veteran
Miscellaneous off topic nonsense binned, back on topic

I'd love to see your write up because all that stuff after the quote above applies to general res maintenance. Isn't that supposed to be a given when discussing nutrient formulas?

Yes it should be "a given" but when running these kinds of specific formulas, there is always much confusion on how to accomplish the add backs etc, especially the lucas where he suggested two different strategies. But, when people are led to believe they can run the same res for several crops then imho, it's time to step in and take a closer look at all the flaws involved.

This deviation of the topic began with someone questioning pH availability per pH charts and how it relates to suggested pH input and maintenance techniques, and it was a very good question related to running add backs or res top off maintenance.

Lets look at a few things now, you have suggested bumping up the pH in week 3 or 4 of veg to 6.0 to 6.1 "to make mag" available for example.
So I'd like to ask, what made you arrive at that suggestion ?
(Mag is a little more available at 5.5 than it is at 6.0 btw)

Could it have been this completely misleading and screwed up pH chart ....
1230915038chart.gif
 
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Haps

stone fool
Veteran
I only know what I have seen here using the Lucas ratio for almost five years. What 10K has written helps me understand some of the precipitates I had a problem with until last year when I started mixing my nutes better before adding to my holding/aging reses.

I also agree that using a res for more than one crop is unsanitary and unthinkable. Also everything should be washed and cleaned between crops if you love your girls. I also would not run a full crop without changing reses if I ever went back to dwc, not because it will not work, but because changing the res is better.

Also, water is different everywhere, there is no one way that is right.
H
 

Hydro-Soil

Active member
Veteran
Lets look at a few things now, you have suggested bumping up the pH in week 3 or 4 of veg to 6.0 to 6.1 "to make mag" available for example.
So I'd like to ask, what made you arrive at that suggestion ?
(Mag is a little more available at 5.5 than it is at 6.0 btw)

Could it have been this completely misleading and screwed up pH chart ....

It wasn't the chart.

I took a 'break' from growing and along the way forgot what pH to set the res at. Actually, your posts were the ones that made me remember 5.2-5.5 being optimum back on CW and OG.

I followed the advice of others (that were starting out with 5.8 pH) and found that their advice was correct for days 20-30. By starting with 5.2 I believe that won't be necessary.
Much appreciated for the reminder. It would explain why I don't remember there being a "Raise the pH" discussion back then. Ever.

My lungs hurt and moving around makes me cough so I'm gonna say Thank you 10k and go to bed again. :D
 

10k

burnt out og'er
Veteran
MarquisBlack posted a question regarding running lucas in ebb & flow with coco.
I've moved it to the coco forum as it's own thread for whomever may be interested.
http://www.icmag.com/ic/showthread.php?t=124644

Coco has it's own special characteristics, is usually ran as a drain to waste because of its tendencies to cause the pH to rise making it somewhat tricky in ebb & flow reservoir maintenance wise. Because of this I agree with Bonecarver_Og (our resident coco specialist) in that coco really should run with coco specific nutrients like Canna for coco.
 

turbolaser4528

Active member
Veteran
hey 10k you wouldn't happen to have a more accurate nutrient availability chart would ya? That fuckin thing misled me as well.

I have one last question, should I try to correct too much food or too little with using as little ph up or down as possible? meaning if im feeding to heavy, add water until ph goes up. And if im feeding too light add nutes + water? rather than adding ph up if my ph drops due to overfeeding?

Because I just dropped my ppm from 1000 to 680 at a .7 conversion and upped my ph from 4.8 to 5.8 using just water and a slight amount of ph up because I ran out of room to add more water. I didn't add nutes, I figure if ph goes up and ppm goes down then I will just add more nutes until I find the the ppm my plants are happy at?

This contradicts Lucas's method of starting rooted clones in 1300 ppm at .7 conversion all the way through flower. I feel as though this would cause massive lockouts and nute burn, am I wrong? Seems it works for some people tho. So many questions, I am sorry for that. I will do more independent research as well as reading your threads.
 

petemoss

Active member
I've seen this chart below but don't know which half is applicable to hand watered coco. The left side seems to apply to soil and the right side is for hydro. But which half should I use for coco?

 

Hydro-Soil

Active member
Veteran
Because I just dropped my ppm from 1000 to 680 at a .7 conversion and upped my ph from 4.8 to 5.8 using just water and a slight amount of ph up because I ran out of room to add more water. I didn't add nutes, I figure if ph goes up and ppm goes down then I will just add more nutes until I find the the ppm my plants are happy at?
I'm gonna go out on a limb here and say that, at 680 concentration you're going to have issues with your plants. Unless you're flowering under T8, T12's or maybe a small HPS perhaps?
Rooted clones can stand 1300ppm @ .7 conversion and I'm sure 10k will agree. Remember that not enough nutes will cause issues, just like too much.

I'm still sick and going back to bed though. Doc says call in a few days if it goes deeper into my lungs. Bleah!
 

10k

burnt out og'er
Veteran
dongle69 wrote:
The medium that you use will dictate what is the ideal ph range.
Coco isn't the same as hydroton, which isn't the same as rockwool, and so on...

Yes true, coco and big rockwool cubes on slabs tend to pull the pH up, which makes them somewhat difficult to manage using chem hydro nutes like flora series multi-part mixes in a recirculating hydroponics system (one with a reservoir to be managed). With these mediums it is much more simple to just run hydro chem type nutes as 'drain to waste', rather than try to manage a chem nute reservoir that's constantly being pulled off spec pH wise by the medium. This is why certain nute manufacturers make medium specific nutrients. Coco for example runs with a lot less difficulty if its being fed with coco specific nutes such as Canna coco which were designed to work much better at cocos natural pH of @ 6

Wait...What! wrote:
There is no one universal cation exchange chart [sorry to burst the bubble] for all growing media.

I agree 100%. but, what bubble are you speaking about?
What I've been trying to address was the pH ranges in the mixed solution reservoirs and how 'if mishandled' can lead to a "damaged" nutrient solution because of the precipitation problems before ithe nute solutions ever get fed to the plants, and how to best manage the reservoir maintenance and chem fert mixing in order to avoid such solution damage.

IE: add-backs, adjustments and topping off and mixing strategies. Running certain additives also plays a role in whether or not the working solution in a mixing reservoir becomes damaged by poor handling methods. The lucas formula (or custom gh flora mixing ratio) advises users methods of res maintenance. It's written for folks running recirculating hydroponics systems. Such add-backs and maintenance never has to be done for folks who are feeding drain to waste or top feeding their soil containers plants, all they'd need to be concerned about is whether or not they've caused nute mixing damage to the cocktail they're about to feed their plants.

Said another way, I hope people aren't confusing what I was addressing about reservoir maintenance and chem hydro nute mixing strategies with pH availability or cation exchange rates for their given mediums. However, this IS the indoor hydro forum, where talk about lucas add-backs and top offs should be discussed. Most soil growers already know their soil will buffer things in a friendly way, but by the same token most soil growers aren't feeding with chem hydro mineral salts anyway.

Haps wrote:
I only know what I have seen here using the Lucas ratio for almost five years. What 10K has written helps me understand some of the precipitates I had a problem with until last year when I started mixing my nutes better before adding to my holding/aging reservoirs

I also agree that using a res for more than one crop is unsanitary and unthinkable. Also everything should be washed and cleaned between crops if you love your girls. I also would not run a full crop without changing reses if I ever went back to dwc, not because it will not work, but because changing the res is better.

Also, water is different everywhere, there is no one way that is right

Thank you Haps :joint:

Turbolaser4528 wrote:
hey 10k you wouldn't happen to have a more accurate nutrient availability chart would ya?


This chart which has been around for decades is a much more accurate depiction of availability at various pH values, then that misleading chart I posted earlier.

Nutrient-Uptake-and-pH.jpg
 

Wait...What?

Active member
Veteran
Does anyone know who originally did the research on that graph? I've seen both Cornell and Stanford cited. Everybody rips it off but nobody gives credit where its due [including the company that used it commercially on the bottle of pH UP]
 
I'm not sure what I learned yet.. but I may a little more confused...

I may NOT go with the LUCAS formula.. Since the MaxiBloom and MaxiGro is similar...

Let me tell you what I have been doing.... lol

from blazeoneup
Indica's
Seedlings and clones 300-400ppm 5.3-5.5 ph
early vegg 500-600ppm 5.3-5.6 ph
middle vegg 600-800ppm 5.4-5.6 ph
late vegg 800-1000ppm 5.5-5.7 ph
early flower 1000-1300ppm 5.5-5.7 ph
middle flower 1400-1600ppm 5.5-5.8 ph
late flower 1000-1100ppm 5.5-5.7 ph
ripening 300-500ppm 5.4-5.6 ph

sativa's
seedlings and clones 250-350ppm 5.3-5.5 ph
early vegg 300-500ppm 5.3-5.6 ph
middle vegg 500-700ppm 5.4-5.6 ph
late vegg 700-900ppm 5.5-5.7 ph
early flower 1000-1100ppm 5.5-5.7 ph
middle flower 1100-1300ppm 5.5-5.8 ph
late flower 800-1000ppm 5.5-5.7 ph
ripening 300-500ppm 5.4-5.6 ph

at this thread....
http://icmag.com/ic/showthread.php?t=26343

I always NEED phUP..... I don't think I can do without it.... I use RO water and MaxiGro and set the pH settle ... usually it starts off well and no ph adjustment is needed (maybe 5.5?) Within a few days the ph DROPS (down) so I add phUP or else it will go down to 4.something...... Sometimes I bring it to 5.8 so it will drop down to 5.2 in case I am not home for a few days...and slowly add more nutes as the plant develops... and change RES. when I go into bloom with new RO water.. and New Nutes... Now sometimes I get deficiencies... maybe it is sometimes I let my system pH drop too much because I am not around... (a GREAT system auto top off and all but no auto PH adjustment)... so i wasn't sure what the def. was from... maybe the few days I slacked on pH.... but that's why i was looking into Lucas formula.. but I would think it would be impossible to NOT add phUp..... My plants usually LOOk great through VEG... it's that 2 months in bloom that I have a little problem.. I get over 1lb on a 1000 watt lamp... are leaves supposed to die? alot? I add phUP and nutes straight to the Res. (that maybe a problem now from reading?)
 

turbolaser4528

Active member
Veteran
awesome, 10k by the looks of that chart it seems 5.0-5.5 is much better than say 5.8 as a lot of people suggest as the starting point, now I understand :)

Hydro-soil - I dropped my ppm down to 680 at .7 conversion which should be way under-nuting my white widow plant which is under a 400watt hps, yet the ppm is still on the rise and ph is still slightly dropping. So i dont get it, the ppm should be going up because this is too little food for them.

And I am using hydroton, should I switch to perlite or maybe neoprene collars to avoid complications from having any sort of ph holding medium???


I think giving the plants less food sometimes would make it grow better, kind of like not always keeping it full but hungry for more!!! if you know what I mean, although I believe 680 is starving them, my hanna meter tells me otherwise so I dont know man.
 
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