Yellow patches?

n4alpaca

Active Member
I'm on my 1st dwc and my plant is starting to get yellow patches on it and I'm having trouble controlling the pH of the water in the rez. I use about 5mL botanicare pure blend pro grow per 16000 mL water and just moved my seedling from soil to DWC a few days ago. Any advice on controlling the pH? also am I using too much fertilizer for a seedling?

http://tinypic.com/r/2n1856d/5
http://tinypic.com/r/24bnotf/5
 

0calli

Well-Known Member
well if you just moved the lil one from soil to dwc then its in shock mode and needs to recover from the switch wait a few days and watch for recovery
 

maps84

Well-Known Member
Man it's supposed to be 20 ml per gallon of PBP, you start with 5 and up it up to 20, 5 steps each week... so why are you feeding like this?
 

n4alpaca

Active Member
It's been long enough that it wouldn't be in shock anymore, and thanks masp I didn't know that i had to get it from 5 to 20 in a few weeks. But the problem of pH remains. How do I control it? with pH down?
 

maps84

Well-Known Member
PH is supposed to rise a few points withing a week that's the normal thing to happen as the plants are taking up nutes. Using too much PH down is bad, so you could go with a bigger res, or buffer your medium, buffer your water (mix 2 days before fertilizing), and feed the proper rate of nutes. If you have some super-thrive around give it a shot too.
 

n4alpaca

Active Member
so I set the pH to around 6 a couple days in advance and mix in 5mL per gallon and slowly add more each day until I get to 20 mL per gallon. Thank you very much.
 

n4alpaca

Active Member
I see what you're saying, everyone always says mix at half strength. Side question; how often should I change the rez?
 

maps84

Well-Known Member
You only fertilize ounce a week, if you wanna give them water in between is good too. I actually have to do it at flowering as they suck water so quickly but in return I the chance to add some extra calmag and sweet and avoid built ups :)
 

maps84

Well-Known Member
Heres's a DWC shot of Botanicares pure blend pro grow in action 3 weeks from clone, I use liquid karma and I always add Aqua Shield. Recipe: label directions.

DWC.jpg

I start at PH 5.5 and adjust when it rises to 6. I do a res change every week or two. I don't have to be on top of the plants, very reliable nutes. Absolutely amazing for DWC. I'd be so happy if bc sponsored me :mrgreen:
 

n4alpaca

Active Member
what medium are your plants in? I'm using Hydroton at the moment. This is my first hydro grow and my second overall, so i'm still trying to get used to the plants.
 

maps84

Well-Known Member
If growing hydroponics I use 2" neoprene plugs/ net pots for cloning, they're basically suspended on air in the aero cloner. then I put them in 3" net pots filled with hydroton in my vertical system wich is a DWC/NTF hybrid. I also grow in soil but I use rapid rooters instead to clone the plants and 5 gal pots. 50% Worm humus / 50% perlite / 10 tbsp of Dolomite.
 

n4alpaca

Active Member
What do you think is happening that could cause A continuous pH drop from 5.7 to 7.5 in a matter of 6 hours
 

maps84

Well-Known Member
Ferts builts up are more likely to rise the PH, howver I've only seen that drastic shifts happening when using unbuffered Hydroton. How do you buffer it?: I soak it in ph corrected (5.5) water for 2-3 days before ever introducing it into my system and rinse as much of the powdery crap out of it beforehand. Depending on what stage of life the plants, fluctuation is as much as 0.5 or per day.
I try to keep my res. somewhere between 5.5 - 6.2
 

n4alpaca

Active Member
That explains it. I suspected that the hydroton was to blame, but I hadn't read anywhere that you had to soak it in pH corrected water. Any recommendations as to what I should do?
 

maps84

Well-Known Member
As I see in the pictures they're still seedlings. So you could try to flood it all in a bigger container and very carefully separate the roots form the hydroton, then set up a small DWC system, no medium just neoprene plugs like the one in you saw in my pic so the plants can recover. When they're back on track and growing healthy leaves, you'd be able to transplant to your original system having your medium already buffered. Reckon that if the roots are too tangled in the medium you could shock your plants even more or even kill them, so be extra carefull, if everything goes right stress should be minimum.
 
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