What's new
GrowWeedEasy.com
You're browsing as a guest. Sign up to join the conversation, share your grows, and get help from thousands of fellow growers — it's free and takes less than a minute.

HELP! pH, PPM, going in and coming out.

rangerjake

New member
I am about 3 days post transplant in the following setup:

3 AF White Widow - 5 gal fabric pots 85% full of Coco/perlite
1 fem Blue Mystic - 10 gal fabric pots 80% full of coco/perlite
1 fem Rasp Cough - 10 gal fabric pot 80% full of coco/perlite

The transplant went from solo cups to these containers, so the girls are still a bit small for their mediums at the moment.

My first feeding at transplant was a light feeding of nutes (GH using the GWE reduced strength schedule) with zero runoff (ph 6.2)

My second feeding a day later was just pH'd water (6.0), more water than the first feeding but still no runoff.

My feeding today I wanted to fully wet out the medium as I figured the plants had adjusted more to the new digs. I gave about .8 gal to each AF plant, and a little more than 1 gal to both photo plants. The feeding going in was at 5.8 and 950ppm

I got runoff from the photo plants which I tested and was at 6.2 and 610ppm.

The last few days since transplant have been stressful conditions as the space has gotten hotter than ideal (70-90f, 26-50% RH) under 2 315 CMH lights on an 18/6 schedule. The tent and plants will be moved in a few days to a much friendlier space with a steady ambient temp of 66f, so that will help a lot I am sure.

Here is what I am looking to figure out:

-the water here is hard. I have 2 sources, 1 is 205ppm/7.0pH out of the tap, the other is 275ppm/7.5pH out of the tap. I will have to predominantly use the 275ppm water but can cut it with the 205ppm if need be. I am using the FloraMicro Hardwater and still have a 900+ppm- and this is only at week 3 on the nute schedule. What else can I do (short of buying whole house RO/filtration systems) to drop that ppm a bit?

-what is the major repercussion to consistently feeding at that 900ppm level?

-what should I be looking for as a runoff ppm level?
 
Not sure if this will be applicable as I've only grown WW in soil and DWC, not coco...I was also using GH hard water micro as well as the regular micro. Our water here ranges from 150-250 ppm and 7.2 to 8.1 pH so I feel your pain. You need to manage your water, or use a line of nutes with better buffering than the GH floro stuff. I've fed the plants above 900 ppm using the regular micro and they fried...at the time I was battling heat and numerous other new grower issues, so there were always some crispy leaves somewhere for some reason. In large part though, they were just overfed. None of my DWC solutions go much above 800 anymore and most of the time I'm in the 650-700 range (500 scale BTW).

I'm lousy at chemistry, but hear is what I've read and how I interpret it. I'm certain someone with a couple of high school chem classes could do better, but here goes.
When I pH adjust hard water, which in my world is full of Calcium Carbonate, using Phos acid, the solution balances to water, carbon dioxide and calcium phosphate. The calcium phosphate is bio available to the plants, and I've effectively increased the "P' portion of my bloom nutrients, so I "should" turn down my bloom nutes. But, in my case, the calcium phosphate, which is insoluble, mostly ends up as salt buildup on my rez walls in DWC, so the reduction of bloom is minimal.

BUT, here's where my understanding gets really thin....This what I "think" happens in coco, I think the roots are sitting in those salts, and coco is already high P and K, so you might see some toxicity, so less bloom nutes required and a target of 650-700 would likely work.

I've learned that when you're experimenting with nutrients, it's better to aim LOW. Adding nutrients to satisfy a hungry plant has way less downside than dealing with toxicity issues; you just have to pay attention to your pH and maintain a tight range.
 
Our water here is 400+ppm and is very hard ,I've installed a whole house filter and it does not bring ppm down but removes chlorine , I feed my girls 4 times a day in coco ,I mix nutes for a ppm of around 800 ,that means my ppm will read 1200 , I know if your ppm is over 300 you are not supposed to use it but I have not seen any i'll effects from it , I could put in an RO filter but I just don't like the idea of wasting more water than I use ,so until I see a problem I'm not worrying about it lol
 
Thanks for these replies. Since I live in a region that sees a fair amount of rain, especially this year, I think I am going to set up some rain catchment buckets similar to this:

https://www.youtube.com/watch?v=g0y0BmEFUcs

Having the rain water would tremendously beneficial. My plants have been trooping along slowly- contending with my unfamiliarity with both GH nutes and Coco medium as well as a stressful amount of heat during the transplant days. But temps have cooled, and very plant friendly home for the tent is being set up with much better temps. So once that variable gets resolved out it'll be easier to get a sense of what damage or challenge the hard water and nutes are giving.
 
Hi Ranger!

i've got very similar water to you; around 7.0 pH and (500 scale) ppm of around 270-280 ; hard water (likely high in calcium carbonates - boiling it leaves limescale).
water source is a private well.

i'm growing hydro with a RDWC system.

in my reasearch for aproaching the optimum NPK balance with the extra's in addition to the GH Flora (hardwater) i found a few things.
- my CalMag has Nitrogen in it. 3-0-0
- Micro is 5-0-1
- Gro is 3-1-6 (in the US it could be 2-1-6)
- Bloom is 0-5-4

One spreadsheet further...

in the 65L water in my system i've put into it (in the order listed):
pH down (Phosphoric acid): 21ml
final pH (after 30 mins): 5.6

Fulvic acid: 95ml (leftover, should be 130ml)
Seaweed: 50ml
CalMag: 10ml
Voodoo: 130ml
Sensizym: 130ml

Micro: 20ml
Gro: 25ml
Bloom: 50ml

Ppm: 480

N____P____K_____N : K
2.0__>1.1__2.9____1_1.5
(spaces... dont show, hence _)

Reason i put P as more than 1.1 is because of the pH down.

my ppm as you see is 480, EC 0.96
a bit high for seedlings (5 days from planting seeds) but they'll adapt (hopefully).


Long story short: I have similar water and i'm using more or less the same nutes you do.

GH recommends: before adding the nutrients to your water, pH the water first to 5.5-6.5. Then add the nutes, and pH as needed.

GH defines <normal> tapwater as EC 0.5 (ppm 250) at pH 8.0 adjusted to 5.5.

See attached PDF from them.

Hope this helps.
 

Attachments

Last edited:
Hi oldjarhead100 ,

pics of the voodoo in the EU
2ml/L

any differences for the bacteria soort and CFU amounts?
 

Attachments

  • photo80191.jpg
    photo80191.jpg
    342 KB · Views: 1
  • photo80192.jpg
    photo80192.jpg
    557 KB · Views: 0
Back
Top