Think it's PH

[StickyIcky29A]

SOIL:

How long has this problem been going on?2 Days
What STRAIN are you growing?Unknown, possibly NL cross
What was the establishing technique? (seed or clone?)clone
What is the age of your plants?3 weeks
How Tall are the plants?10-12 inches
What PHASE (seedling, vegetative or flower) are the plants in?Veg
What Technique are you using? (SOG, SCROG etc) None
What size pots are you using? (Include how many subjects to pot)16oz cups
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?)Sphanum Peat, Vermiculite, and Perlite
What Nutrient's are you using?How much of each with how much water? How Often? *Knowing the brand is very helpful* Pure Blend Pro, following directions
What is the TDS/EC/PPM of your nutrients used?
What is the pH of the "RUN-OFF"? 4.7
What method of pH test was administered? Using Strips? pH pen?Pen
How often are you watering?As needed
When was your last feeding and how often are you feeding?7days
What size bulb are you using?4 23w CFL
What is the distance to the canopy?2 inches
What is your RH Factor? (Relative Humidity)50-60
What is the canopy temperature?78 at highest
What is the Day/Night Temp? (Include fluctuation range)
What is the current Air Flow? (cfm etc.)
Is the fan blowing directly at plants? One
Is the grow substrate constantly wet or moist?no
Is your water HARD or SOFT? RO water
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? RO
Has plant been recently pruned, cloned or pinched? They are clones
Have any pest chemicals been used? If so what and when?No
Are plant's infected with pest's? No



Lots of stuff to fill out there man...Okay, to boil it down: I think it's PH problem. The new growth is a little yellow. And I have a few spots.(sorry no pics) Peat in my mix is low ph, and i did not add a buffer. Run off is about 4.7.


I'm going to flush to solve the problem. My question is should i flush with plain R/O, or Up the PH a bit and do this? Wasn't sure if flushing with 7ph water would raise the peat PH.

 

[Weedninja]

Are you using a commercial mix or did you prepare it yourself? If you are using your own soil mix, read on:
Peat itself is pretty acidic,and perlite and vermiculite are basically neutral. So if you don't sweeten the soil mix with some lime or oyster shells or something, you can flush all you want and the peat is just going to keep making it acidic.

 

[StickyIcky29A]

Went ahead and transplanted them into Fox Farm Light Warrior. Hopefully that will fix the problem.

 

[Weedninja]

I was never really a big fan of shocking plants by transplanting into an entirely new medium like that, but I hope it works out for you. Don't give up on the soil-building, it can be very rewarding and its alot cheaper than buying it pre-packaged.

 

[FreezerBoy]

Peat itself is pretty acidic,and perlite and vermiculite are basically neutral. So if you don't sweeten the soil mix with some lime or oyster shells or something, you can flush all you want and the peat is just going to keep making it acidic.

I used to keep fresh water amazons. They LOVED acidic water. I'd lay an inch of Peat under the gravel bed and the plants and fish thrived. I'd swap out the peat every 2-3 years That stuff stays acidic a long time.