Nutrient ppm profile for cannabis-Where to start?

[Dilbert Do]

Hi. I'm new here. My intro thread is here: https://www.icmag.com/ic/showthread.php?p=5316192#post5316192

I'm putting together a bubble bucket DWC grow in a GL40 tent (roughly 16"x16"x48"). I have grown a single plant in soil using a stealth PC grow case. I'd like to use hydroponics this time.

I would like to mix my own hydro nutrients to save money, but I don't know what the final concentrations of the nutrients cannabis needs should be in my bucket.

I have already have a pound of planted aquarium nutrients. Namely:
Potassium sulfate 0-0-50
Mono potassium phosphate (KH2PO4)
Potassium nitrate (KNO3)
Plantex CSM+B

Plantex CSM+B is for micronutrients and contains:
1.50% magnesium
0.10% chelated copper
7.0% chelated iron
2.0% manganese
0.06% molybdenum
0.40% zinc
0.04% boron

So, what final concentration of each nutrient in the hydro solution that should I seek?

 

[c64]

i hope this helps you further.

mono potassium phosphate (KH2PO4) have 0-52-34 (n-p-k)

i give 2g to 10 liters. corresponding to approximately 10 ml per 10 liters pk13/14 hesi.

 

[Dilbert Do]

I'm trying to calculate how to mix nutes with HydroBuddy. Basically what I want to know is what ppm of each nutrient should I shoot for? Namely:
N
P
K
Mg
Ca
S
Fe
Cu
Mo
B
Mn
Zn

 

[jayjayfrank]

108 N - 42 P - 114 K - 74 Ca - 22 Mg - 17 S

i have been using that as reference lately

 

[rives]

What is the composition of your water? Are you using tap or RO, and if you're using tap, you are going to need to know the Ca & Mg levels. Some is too high straight from the tap, and others (like mine) has virtually none.

 

[Dilbert Do]

Thanks, jayjay.

Rives, I plan to use tap water. I won't be able to install RO for this grow. I may have enough Ca and Mg already because the water in my area is pretty damn hard. I don't have measurements yet... haven't purchased an EC or pH meter, as I'm still trying to figure out which one to get. What are the target Mg and Ca values you shoot for?

Anybody else have numbers?

 

[dizzlekush]

I would like to mix my own hydro nutrients to save money, but I don't know what the final concentrations of the nutrients cannabis needs should be in my bucket.

I have already have a pound of planted aquarium nutrients. Namely:
Potassium sulfate 0-0-50
Mono potassium phosphate (KH2PO4)
Potassium nitrate (KNO3)
Plantex CSM+B

Plantex CSM+B is for micronutrients and contains:
1.50% magnesium
0.10% chelated copper
7.0% chelated iron
2.0% manganese
0.06% molybdenum
0.40% zinc
0.04% boron

So, what final concentration of each nutrient in the hydro solution that should I seek?

First off, to answer your question, I suggest starting with Spurrs formulations and changing them as you see fit when you want:
https://www.icmag.com/ic/showpost.php?p=4707360&postcount=2

Note that for Ca, Mg, and S that he is formulating for RO water and typical drain-to-waste usage. You said you use 'tap' which i guess means municipal water, so you should be able to find out you Ca, Mg, S, Alkalinity ppms online or from you water company for free .

Now for my advice, you should really buy calcium nitrate (CalciNit), magnesium sulfate heptahydrate (Epsom Salt), and AgSil 16H (Potassium Silicate), Citric Acid for pH down (and proper P and Ca availability) and Potassium Carbonate (NOT Bicarbonate) as pH up and to act as a pH buffer with Citric acid. There will be links to buy most of those on the first post in the 2nd thread or deeper in the 1st thread.

You should REALLY read these two threads:
https://www.icmag.com/ic/showthread.php?t=222646
https://www.icmag.com/ic/showthread.php?t=232715

Best of Luck! PM me with any Q's and feel free to join in on either of those threads if you want. They were meant for people doing what you're doing.

 

[rives]

Thanks, jayjay.

Rives, I plan to use tap water. I won't be able to install RO for this grow. I may have enough Ca and Mg already because the water in my area is pretty damn hard. I don't have measurements yet... haven't purchased an EC or pH meter, as I'm still trying to figure out which one to get. What are the target Mg and Ca values you shoot for?

Anybody else have numbers?

I have the best luck with Mg in the 50-80ppm range, and Ca around 3-4x that. I use tap water, but it only has 1.1ppm of Mg. and 4.4ppm of Ca, so it all needs to come from the nutrients. If you are on a municipal system, they probably have a water analysis that you could request. It may even be on line. *edit* - whoops, see dizzlekush just touched on this.

 

[Dilbert Do]

After reading through the thread, I think I want to go with a less complicated approach for my first hydro grow. If all goes well, I'll try mixing my own nutes after having a couple successful hydro grows.

I'd like mixing my hydro liquid to be a simple process (as few components as possible), but also be inexpensive. (I know, I know. Speed, price, quality: pick two. )

A summary of my tap water follows:


pH: 8.5-9.0
Total hardness (as CaCO3): 80 mg/L
Total hardness (as CaCO3): 5 grains/gal
Fluoride: 1.0 mg/L
Sodium: 64.1 mg/L
Chlorine: 0.6-2.4 mg/L
Copper: 0.06 mg/L


I think I can get away with General Hydroponics MaxiBloom using 7g/gal (commonly used halfassed Lucas formula) for nutrients and citric acid to bring my pH down to around 5.8.

If I allow my tap water to sit out to evaporate the chlorine, could I grow using only tap water, MaxiBloom, and citric acid?

 

[Hydro-Soil]

After reading through the thread, I think I want to go with a less complicated approach for my first hydro grow. If all goes well, I'll try mixing my own nutes after having a couple successful hydro grows.

Good choice! I see a bright future for yourself.

I'd like mixing my hydro liquid to be a simple process (as few components as possible), but also be inexpensive. (I know, I know. Speed, price, quality: pick two. )

A summary of my tap water follows:


pH: 8.5-9.0
Total hardness (as CaCO3): 80 mg/L
Total hardness (as CaCO3): 5 grains/gal
Fluoride: 1.0 mg/L
Sodium: 64.1 mg/L
Chlorine: 0.6-2.4 mg/L
Copper: 0.06 mg/L


I think I can get away with General Hydroponics MaxiBloom using 7g/gal (commonly used halfassed Lucas formula) for nutrients and citric acid to bring my pH down to around 5.8.

If I allow my tap water to sit out to evaporate the chlorine, could I grow using only tap water, MaxiBloom, and citric acid?

The MaxiBloom is a great choice to start hydro with... used it for years.

I suggest you bring your pH down to around 5.4 or 5.2 (depending on how often you top off your res). You'll want to allow the pH to rise to around 5.8-6.0 before you drop it back down again.

Only citric acid?? Dunno about that one... other than you'll most likely be adding it constantly. Perhaps there's a thread around here on the subject.?

Stay Safe!

 

[Dilbert Do]

Should I use some other type of acid? I don't know much about selecting a pH adjust, except that I would want to avoid anything that will make salts precipitate out of solution.

Will my water's natural hardness have a buffering effect on pH even after being lowered by the addition of an acid?