can the PH be corrected?

yes but it really doesn't matter much apparently..........
It's definately not something I've ever worried about in soil.
Totally different in a hydro set-up.
I find mine rises .3 or so daily, but that's a recirculation system.
Not sure if it's any different in a system that doesn't recirculate the solution - but it would be interesting if someone can confirm either way

 

I ve read that ph should be about 7 or as close as you can get it. I leave my tap water set 24 hours before giving it to plants. I use a soil PH kit i bought from lowes about $11. If soil is acidic below 6 use a little lime about hlf cup for 3 gallons or until you reach 7. Check PH every 3 weeks. Never had to go the other way. This seems like its working for me.

 

pH is only defined for aqueous solutions.
When you push your pH meter into the soil, it is actually reading the pH of the water absorbed in the soil. Push your pH meter into dust dry soil and the needle doesn´t move.

 

The optimum pH for a soil grow is 6.3-6.8, ideally tending to the lower end during veg and graduating to the higher end during flower. Reality is keeping pH between 6-7 throughout the grow should be fine. There are many easy ways to adjust the pH:

To lower ph in soil: Phosphoric acid, vinegar, lemon juice, sawdust, composted leaves, wood chips, cottonseed meal, leaf mold, peat moss, or PH Down.

To raise pH in soil: potassium hydroxide, dolomite lime, hardwood ash, bone meal, crushed marble, crushed oyster shells, or PH Up.

 

Toasty, good post, +rep

 

Very diluted battery acid from ur car battery works as ph down.

Don't attempt to use it without some means of measuring the ph Before u add it to ur soil / hydro solution.

Get a squeezy bottly, attach some tubing to the top & squeeze some air out.
Stick it in the battery & suck up some acid.
Be carefull -it's Very strong!

 

Battery acid!! Sulphuric acid!! Be serious.

 

works for me

drip some battery acid on ur skin = nothing happens (but obviously wash ur hands after)
drip some phosphoric acid on ur hand - bought from a hydro shop = instant blistering burns.
make ur own choice

same with ph+ = sodium hypochlorite = Very caustic & can cause nasty burns yet u can buy it at hydro shops or online.

With any ph- or +, be sure to add the chemical to water & NOT water to the chemical.
Wear eye protection & preferably gloves too (pls)
Only takes 1 splash in the eye & u could be permanently blinded.

 

You haven´t mentioned the relative concentration of the acids, which is all important.

And when you put a nail in Coke it will dissolve because the drink contains phosphoric acid.

And when 19th century ladies threw acid in the face of a rival it was always vitriol, sulphuric acid.

 

that's why i stated that u should dilute the acid first - as in a Very dilute solution.
Same as u would use a Very diluted solution of phosphoric acid.
If u just poured either of them directly onto plants undiluted, it would dissolve them with a sizzling cloud of either sulphur or phosphor flavoured fumes = not advisable

If someone is in any doubt they should only use premixed + / - solutions bought from a reputable hydro shop.
Read the instructions & if u still don't understand, talk to the supplier

I R mr fkin chemical so shit like this is all in the fun for me, but I understand how some people are scared of the word ACID

*incidentally, have u tried smearing a dull corroded coin in tomato sauce? try it...........
Also, try dropping a piece of tinfoil in bleach

 

Diluted or not, why go to the trouble of getting acid out of your battery (careful not to splash any in your eyes) when you probably have a bottle of lemon juice (citric acid, and organic too ) in the fridge?

 

Yes, amazing results!!!!!!!!!!!!!!!!!!!!

 

tried using lemon juice Toasty, but found it's back up again within a few hrs - dunno why
phosphoric acid is best ph- though without a doubt as it leaves phosphorous (hydr)oxides behind which is an essential part of a plant's diet.

I like to experiment tho

 

Agree there, Num, phosphoric acid is the one I would use if I had to lower pH. But I am fortunate, I do not have problems with pH, my water and organic ferts keep it just under 7.

 

i use phosphoric as im in a hard water area...ph settles to around 8 on its own...
i find ph tends to fluctuate more rapidly in a smaller res...larger reservoirs (50l +) tend to stay more stable once adjusted...thats just my experience....

 

do u find that ur ph is more stable in 12-12????
exposure to light seems to have a big effect on ph imo

for the same reason u outlined, I joined up my 4 25l bubblers to give er..... a 100ltr res.
Should save having to adjust ph of each tub separately every day :/

 

i cant say ive noticed much difference in light schedules...but it could be the size of your res exagerating the effect...joining your reservoirs should help there...
i also have a settling tank where i let my tapwater sit before i make adjustments ...flip top bin is a good size for res changes etc...im a dab hand with a siphon..lol...