Jack's/peters Hydroponic In Undercurrent

[MurderVille]

My flowering room sorted itself out, I just changed my ratios around to what I was using before.

I understand why you created this thread. I was just saying I ran into issues feeding at this ratio Jacks has.

These are the yellow tips I was talking about. Only on its growing tip. Its at 1.0EC of feed.

View attachment 658004

It progresses to this marginal and then interveinal yellowing.
View attachment 658005
Almost looks like Mg but its on the top,of the plant.

Probably potassium....try using a mild dose of a pk booster and see if it improves.

 

[MurderVille]

Awesome.. it's cool to meet others that rdwc, or under current.... Most of the guys here I bullshit with use soil or coco. ..
I'm usually like dang soil takes a lot of work and their like hydro is so confusing..
It's actually pretty simple. It's more about trying to stay inside certain parameters. ..

From what I've come to learn, it seems like thats all you need to do is stay within set parameters no matter the medium, it just seems that we growers prefer to complicate everything.

 

[MichiganMike]

I'm starting this thread to help shine some light on the correct Recipe information for Jack's/Peters Hydroponic in the Undercurrent DWC system.

After reading an entire thread of 73+ pages about using Jacks/Peters Hydroponic on this forum, it still left me scratching my head with few concrete answers. Instead of just throwing in the towel and heading back to the hydro store for an overpriced bottle of magic, I decided to purchase Jack's Hydroponic and CaNO3 and throw caution to the wind.

With so much information being offered by many, I quickly learned that much of it is not geared toward the undercurrent system, and further, few people actually know how to consistently harvest using this undercurrent method.

Low EC, High EC, deficiency, toxicity, low ph and high ph...there are enough methods and opinions out there to leave you pulling your hair out as you watch your harvests quickly diminish due to non-proper methods and poor plant nutrition..I have read and have actually seen people alleging to have success in all of those given scenarios above. As a result, I have followed and attempted these theories but have never had the consistent level of production that I was after. Until now.

After talking to Current Culture reps and technical advisors there, and a few others, I was constantly told to run a lower EC, and when I tell you I never had success with that method, it is a F*%KIN understatement. Statements like these had me chasing my tail around going crazy for far too long.

Undercurrent systems are said to be extremely efficient, but I don't care how efficient it is, it cannot change a plants nutrient profile/nutritional requirements just for the sake of increased availability of elements in the root zone. The plants we grow have specific nutrient profiles with tolerable ranges of each micro and macro element, so to believe that the undercurrent system is so efficient that it will allow for low ECs, is essentially saying that these plants no longer have the same nutritional needs. Does this claim make sense scientifically? I think not.

Assuming that undercurrent systems are efficient and allow for the plants easy uptake of nutrition through the roots, then let us create a nutrient profile based on the minimum requirements using Jack’s/Peters Hydroponic.

Using the “Nutrient Solution Composition” chart at the bottom of page 304 in Jorge Cervantes book “Marijuana Horticulture - The Indoor/Outdoor Medical Growers Bible” you can see the basis for this formula. In order to give your plants 98% of your plants minimum requirement, the dosage instructions will be:

100% SOLUTION FORMULA

3.7 grams/gallon of Jack’s/Peters Hydroponic and
2.44 grams/gallon of CaNO3

This formulation delivers everything your plant will need with a slightly lesser dosage of nitrogen. The EC of this formulation comes in at 2.0 which seems high for undercurrent, however, it is exactly what the plants require based on the plants NUTRIENT PROFILE.

DO NOT USE THIS 100% SOLUTION ON SMALL OR IMMATURE PLANTS AS YOU RISK FAILURE DOING SO. ALWAYS DILUTE BASED ON PLANTS STAGE OF GROWTH.

Thank you for starting this post. I have built a RDWC and wanted to use Jack’s and think this will be very helpful.

 

[MichiganMike]

I was wondering how often you folks change out your entire Rez? I also see that some top off with water only, some with various nutrient solutions, and others both separately. What are your opinions? I have been reading that some people infrequently do a complete change. Interesting stuff. I am still building room and have never used the RDWC I built. I did use Peters the last time I grew, about 30 years ago! Sorry to ask so many questions. It will hold approximately 90 gallons.

 

[QuarterbackMo]

Funny I came across this I’ve been playing with peters lately along with raw nutrients seeing what works and experimenting with it. For the record I use house and garden in my real grows still so I can’t say I’ve done runs with it but I’ve been testing different plants with it and plan to flip one soon that’s Peters and supplemental iron Etda, p, and k only and see what happens.

For the low N you can either foliar feed it once per week while it’s growing or supplement magnesium sulfate for magnesium nitrate in the grow phase which would be the same as using something like botanicare calmag. RAW nutrients has foliar recipes for N supplementation if you’re interested.

It’s also a little short on iron @ 3ppm most commercial nutes use about 10ppm if I’m not mistaken. You can easily fix this supplementing etda iron though.

Other than the iron and low n for aggressive growth I think you can probably slide on the rest of the micros in the base ferts.

I’m going to try playing with adding phosphorus in veg to make more of a starter fertilizer next and gonna try to tweak p and k respectively in bloom.