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Store bought water or De-ionised water

Thread starter #1
So i've figured out my water must be contaminated in my taps. I start out with ph 6.6 soil and no matter if I use organic or synthetic nutrients the soil ph goes way up and I get lockout It's usually up to about 8-8.5 by the 4th week of flower. The leaves start to go yellow and necros the fuck up and I loose the most part of my yield. These are leaves from the bottom (Which i understand is usual) and the middle moving up to the very top bud leaves. It's heart breaking. According to my faggy ph strips the water ph is 7.5 or 8. I am thinking of getting some store bought water or maybe some de-ionised water. I cannot afford an RO system.

Will deionised water be ok for plants?
Anyone got any ideas why this shit is happening?
I am feeding Biobizz grow - bloom - topmax and shogun calmag
I am using biobizz allmax
It only seems to happen during flowering.
cheers
 

Antics

420 Member
Do you PH your water down to 6.5 (+/- depending on soil PH)?
Do you test your soils PH before watering and feeding?

A digital PH meter should work great for all your testing needs, and will be accurate. If budget is an issue, an analog meter can be helpful, but keep in mind it's not as accurate. I personally have been using a cheaper analog meter, and it has helped me through 2 successful grows now.

I use tap water for everything, I just let it sit for at least 24 hours before using to allow the chlorine to dissipate.

Have you always been growing the same strain? The yellowing indicates PH lockout, OR that the nitrogen is gone from the soil, and the plant is using its own nitrogen stores to feed itself. Verify soil PH to find out which one it is. I suggest using a PH adjustment product. I've been using General Hydroponics PH down, as my soil PH constantly climbs upwards, and would probably go into the 8's if I wasn't PH'ing my water and nutes.

Your test strips will still work well for testing runoff, your water PH, and nute mixture. But I'd suggest a way to test the soil itself. Or you can water until you start to see runoff out of the bottom of the pot, and as that first bit of runoff collects, use your PH strip to test that first bit of runoff. That will also be a good indication of what's happening in your soil, PH-wise.
 
Thread starter #3
I have a soil ph meter, its usually between 8 and 8.5 depending which plant i test. I think I will invest in some ph down and a water meter when i get some cash. I had heard it was a bad idea, but if you are using it then I'll try it. But why does the ph climb? It must the water right? De ionised water is pure as fuck and pretty cheap too. couldn't it be a good solution in the long run if it's just the plant nutrients solely - no contamination's?
 

Antics

420 Member
Sorry for the delay, I had to do some quick research..
I found this online, I corrected typos/grammatical errors, and removed irrelevant information:

What Causes Soil to become Acidic or Alkaline?

1. Parent Material - Soils are made up of ground up rock and the type of rock dictates the natural pH of the soil. alkaline rock like limestone creates alkaline soil (range of 7.0-8.6) and acidic rock, rock containing more silica, creating acidic soil. (I have not been able to verify this second part)

2. Rainfall/Watering - Rain leaches basic elements such as calcium and magnesium from the soil. Therefore you will find areas with high rainfall generally have acidic soil while dry areas tend to have alkaline soil.

3. Fertilizers - Some fertilizers tend to make the soil acidic. Ammonium urea is an example.

4. I have read that the escape of dissolved gasses in water can also affect PH.
 
Thread starter #5
Hey cheers for this man. After a little more research myself I have decided to follow your advice and get a ph meter and some ph down. I am also gonna get some de-ionized water and use it on 2 side by side clones of the same strain for reference - I'll still ph it from 7 to 6 though.

Cheers again
 

Tead

Well-Known Member
My tap water comes out of the tap at 8.3.
I fill 5 gal buckets with tap water, let it set (usually 2 days min) to let the dissolved gasses dissipate.
When I need to do some watering/feeding I fill a 1 gal plastic milk jug with some of the settled water, add my nutrients to the 1 gal container, mix well, then adjust the PH of the water/nutrient mix (6.5 for soil, 5.8 for hydro). The nutrients or other amendments will have an effect on your ph.

Many folks use de-ionized water... but I haven't seen folks do a full grow buying water from the store. I think most de-ionized water users have a filter system on their house that provides de-ionized water. It can get pricey and inconvenient to do a multi-month grow buying water from the store. For example, when you flush your plants, you'll typically go thru several gallons of water.

Don't trust your soil ph meter. They're just useless. Go get a real ph meter and use it to test your water going in and your runoff.

There are some amendments you can add to your soil to more permanently adjust the PH, but I would not start thinking about those yet. You really don't currently have the tools to get a handle on what your PH numbers actually are... so adding things at this point would seem very unwise.

A little personal story...
We all get lazy at times and sometimes forget things. Many years ago, I had somehow gotten into the habit of not adjusting the PH of the water going in. I was growing in Miracle Grow soil for the sake of ease, so I was just watering. I swear, it took me about a year of wondering why my plants were sucking so hard. Once I adjusted their PH for a few waterings the plants turned into much healthier babies. Lesson learned.... ALWAYS get the PH right....everything else depends on water at the proper PH.

Summary: Go get a PH pen. You really just can't move forward without it.
 

Antics

420 Member
Don't trust your soil ph meter. They're just useless. Go get a real ph meter and use it to test your water going in and your runoff.
I have to politely disagree. The soil PH meters aren't completely useless, but I think it's important to emphasize that they are not as accurate as the digital meters. Unfortunately not everyone has the budget, or availability to purchase a better meter. I know they start at only $20, but some folks are on fixed/limited incomes, and a cheap analog meter is better than no meter.

I have been using one of the cheap meters for 2 complete grows, and going on a 3rd. That meter helped me yield over 3 ounces on 2 plants with CFL lighting.

Is it the best meter I could use? Absolutely not. Any digital meter will run circles around it.
But did it help me grow successfully? Definitely.
 

Tead

Well-Known Member
Unfortunately not everyone has the budget, or availability to purchase a better meter. I know they start at only $20, but some folks are on fixed/limited incomes, and a cheap analog meter is better than no meter.
Excellent point. While craptastic, they do provide some information as to trending... but not much else.
While I can see using one on an ongoing monitoring basis, it seems like it would be really hard to address any issues that may arise using it's data. I sure wouldn't try to do any ph adjustment based on the info from one.
 
Thread starter #10
Will do antics. I'll let the clones grow a little more then start a 10 week journal. I am going to get a Digital Ph meter but I've just got some bottled water for Very cheap and its source ph is 6.2 so i'll try that on a third plant in the comparison.

Cheers to everyone
 
Will do antics. I'll let the clones grow a little more then start a 10 week journal. I am going to get a Digital Ph meter but I've just got some bottled water for Very cheap and its source ph is 6.2 so i'll try that on a third plant in the comparison.

Cheers to everyone
Sounds like a good plan. If you have the money for it, the digital meters are the best you can possibly use.
And if you haven't grown yet, this topic will have a lot of great information to help you through the growing process: http://www.420magazine.com/forums/h...-grow-marijuana-everything-you-need-know.html
 

jinn

New Member
something that might help you, is this lovely little contraption from ledtester!
http://www.420magazine.com/forums/d...ll-scale-grower-cheap-portable-effective.html

But like everyone else has been saying, a decent digital ph meter is worth its weight in gold! I bought my ph, tds/temp, and ph up and down all for under 50$ us on amazon. While they may not always be required, its much better to have them and not need them =p
 

Fuzzy Duck

Well-Known Member
Mmm pretty normal for leafs to turn yellow from bottom upwards during flowering...


With cheap PH meter probes like this.



They do tend mess up if left in the soil for prolonged periods of time, hence probe should be removed after reading is taken to keep them accurate and cleaned.


From my own experience soil has a natural PH buffering effect & general returns to ambient PH value of soil after several hours or so after feeding with nutrients/water.

So i may ask...

When do you test soil PH is it after direct feeding/watering, normally suggest a PH change by the way in the soil.

Or do you test soil PH some 12 hours later for example & if so you may notice a drop or return to the ambient PH level of the soil !