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SeaLevelGrower
11-27-2010, 10:02 PM
If your soil is either acid or alkaline, would you need to adjust your water/nute pH accordingly? For instance, my girls are suffering from lockout due to soil being slightly alkaline. In order for my runoff to come out at a pH of 6.5, I had to flush with plain water pH'd at 5.1. My question is, should I always feed/water with a pH of 5.1(+/- depending to run off)? Or do I continue to feed/water with a pH of 6.3-6.7? The goal is to have a soil runoff pH of 6.5 correct? I was feeding/watering with 6.5pH, but my run off was approx 7.1 pH.

Thanks.


SLG

GetThisOrDie
11-28-2010, 06:56 AM
What kind of soil are you using?

GetThisOrDie
11-28-2010, 07:21 AM
You should be able to correct it with a good flush with the proper ph water. You can also continue to water/feed at an adjusted ph until the runoff is correct. Then proceed to use corrected water again.

Make sense?

Here is a sticky which the topic is explained more by someone with much more experience than me.

http://boards.cannabis.com/plant-problems/153522-soil-runoff-ph-flushing-correct-lockouts-why-how-do.html


I asked your soil type because some commercially available soils use certain ingredients that can gradually change the PH over time. Like pine bark chips.

canniwhatsis
11-28-2010, 08:35 AM
My experience with FFOF is it is alkaline, I feed inbound at 6.0 and get a runoff of about 7.0-7.1 on fresh soil tho over time that wears down.

I try to keep inbound between 6.0-6.5 and haven't really had any problems.


That is until recently when my Pen got out of calibration and I started PHing inbound to 5.5 and less! :mad: (Didn't know it because the pen was whacked)

Now I'm still suffering the effects of it, even tho my inbound is in line again. :(

Inbound of 6.0, Outbound of 7.1 is a soil average of 6.55...... that's pretty f'n close in my book! :jointsmile:

canniwhatsis
11-28-2010, 08:42 AM
You should be able to correct it with a good flush with the proper ph water. You can also continue to water/feed at an adjusted ph until the runoff is correct. Then proceed to use corrected water again.

Make sense?

Here is a sticky which the topic is explained more by someone with much more experience than me.

http://boards.cannabis.com/plant-problems/153522-soil-runoff-ph-flushing-correct-lockouts-why-how-do.html


I asked your soil type because some commercially available soils use certain ingredients that can gradually change the PH over time. Like pine bark chips.

Read the first few posts there,... good info! :thumbsup:

I'm gonna have to set some time aside to read the rest of that thread, ATM I'm not so concerned with outbound (runoff) PH as it doesn't seem a very accurate measurement.

Just my :glugglug: $.02

SeaLevelGrower
11-28-2010, 09:22 PM
I will start off with an ingoing of 6.0 like you said and see how that affects the run off. If my run off is still high (+7.0 pH) should I try a little lower on the ingoing...say 5.8 or so?

The soil is basic crap from the hardware store...next round of soil will be "ROOTS".

tHANKS

MadSativa
11-28-2010, 10:25 PM
if your soil ph needs to go lower add some sulfur or aluminum sulfate, sold everywhere, everywhere like nursery's, some walmarts and home depots.

SeaLevelGrower
11-29-2010, 12:02 AM
@Madsativa: how do I use them? Im not sure exactly what the pH of my soil is. I got a good deal on some basic potting soil at the hardware store, so I added some perlite to it and viola! It doesnt mention what the pH levels of the soil are though...but I can tell that it is alkaline after the lockout problems I am having. How can I test the pH of the soil before I even use it?

MadSativa
11-29-2010, 12:12 AM
to check soil Ph usually you can check your runoff or waste water (water from the bottom of the pot). to do this water the plant let it sit for about 10 mins then re water so you get a good cup or 2 of the runoff, then collect it. let the sediment settle for about 5-10 mins, then use a Ph tester to check the Ph of that runoff water (water from the bottom of the pot).
Usually everyone uses a Ph tester which is a drop solution and a little vial. there are different Ph testers with the best being digital, but the droppers is a standard, its what almost everyone uses, especially when starting the kit is about 6 dollars vs 100 for a digital Ph pen type.

pH Test Kit by General Hydroponics | pH & TDS Testing (http://www.bghydro.com/BGH/itemdesc.asp?ic=TEPHKITGH&eq=&Tp=)

more than likely you need to add some dolomite lime to you pots , but do a Ph test first, dolomite can be added to the topsoil so no need to dig up the plant. dolomite lime raises the Ph of the soil as most soil is low in Ph

MadSativa
11-29-2010, 12:20 AM
Read the first few posts there,... good info! :thumbsup:

I'm gonna have to set some time aside to read the rest of that thread, ATM I'm not so concerned with outbound (runoff) PH as it doesn't seem a very accurate measurement.

Just my :glugglug: $.02

its not but if you have a reading of 4 or 8 then their is the problem. accuracy is better with a digital pen then a dropper kit but runoff is important in diagnosing.

MadSativa
11-29-2010, 12:25 AM
yeah I just saw it now I didn't know you mixed your own soil which is good lots should do this, but you need to add dolomite lime to get Ph soil higher, tree bark is to lower your Ph you need to raise it. when mixing your own soil most just us worm castings perlite and dolomite lime, you left the dolomite out so now the Ph is not set correctly I think if you add some dolomite to the surface you should be OK, but do the Ph test and make sure. dolomite is avalable at any hydro stor or nursary sometimes even wallmart

GetThisOrDie
11-29-2010, 06:53 AM
The drop kit can be very misleading when testing runoff. Especially if the runoff is discolored.

PH pens are only 15-20 bucks.

MadSativa
11-29-2010, 08:00 AM
15-20 really here for a good one it is about 40 minimum and then you have to get calibration solution and cleaner and keeper solution. to get a complete tds ec and ph tester here it is close to 400 when all is gotten.

GetThisOrDie
11-29-2010, 03:22 PM
WHAT?!

pH 600 Water Tester Meter Milwaukee pH600 Hydroponics - eBay (item 370459245051 end time Dec-22-10 12:42:53 PST) (http://cgi.ebay.com/pH-600-Water-Tester-Meter-Milwaukee-pH600-Hydroponics-/370459245051?pt=LH_DefaultDomain_0&hash=item56411779fb)

first one on the list. 20 bucks.

ppm meter is another 20.

The calibration packets are 3 for 5 bucks. Just ordered some the other day. Bought the storage solution once and thats it... I store it in tap water now.

SeaLevelGrower
11-29-2010, 07:17 PM
I have a digital pH pen already...Oakton brand.

MadSativa
11-29-2010, 10:52 PM
thats a good deal, but Milwaukee is not one I am familiar with, I will only trust oak ton, Hanna, and blulab, with blulab and hanna being the ones i know even when they break I have a chance of getting a new one or a replacement. but that is a good deal, add a tds in their and then about 50-60 bucks in solution and;... well now I see it is just about 20, bucks cheaper but still not too bad. I really like the all in one monitors, one you don't need as much solution waste and 2 it is much easier to get 3 readings at one time then 3 separate readings, but I like the 20 dollar option too.

polishpollack
12-03-2010, 02:47 AM
pH can range from 5.5 to 7.0 typically without much trouble. Roots will probably be much better but I don't know if it's your pH there SLG, or something else as 7.1 doesn't sound terrible. Got any other circumstance?

Dutch Pimp
12-03-2010, 03:27 AM
:)...

GetThisOrDie
12-03-2010, 03:33 PM
Cool chart dutch!