cary schellie
Active Member
Im using pro mix, when I add my nutes I ph them to 6.5, when i check the run off the ph is low (under 5).Should i be concerned? Should I add more dolimite lime? I seems lately ive been getting some nute lock out.
ph issue
- Thread starter cary schellie
- Start date
jondamon
Well-Known Member
Dolomite lime will help but have you considered that you may have salt build up causing the low pH coming out.
Do you test your nutrient strength?
Could be worth backing off the strength on your feed days and running a little more water than normal in your water days.
I take it you have some plain water days?
J
Do you test your nutrient strength?
Could be worth backing off the strength on your feed days and running a little more water than normal in your water days.
I take it you have some plain water days?
J
Check the pH of your soil (as opposed to your runoff) after you have watered it once with plain water with plenty of runoff.
If the soil has a low pH, under 5.5, then water with cal-mag. Dolomite is too slow to just add as a top dressing.
cary schellie
Active Member
i use fox farm 6-4-4 once a week and water once in between, so I shouldnt have salt build up
cary schellie
Active Member
are those ph soil meters reliable or should i use the liquid testers, my buddy bought a ph meter for 15 bucks, i dont think it even works right, so flushing and adding cal/mag will fix low ph in soilless mix, i know peatmoss naturally has a low ph, thats what i use
Yes watering with Cal/Mag will raise the pH of the soil. But do measure your soil ph first to make sure thats what the problem is. Measuring the pH of runoff is unreliable.
I never used soil ph meters, so don't know. I have used papers, drops, and digital lab meters. Irregardless of which type I always take a soil sample, mix well with distilled water and then measure the solution with the tester.
rollinronan
Well-Known Member
The pH of the run off = the pH of the water going in + disolved solids from the soil (ie crystaline salt buildup)
keep watering the pot with pH 6.5 water until the pH of the runoff is equal to the pH of your water going in
only then can you be sure that there is no nute buildup and the soil = pH 6.5
Actually thats backwards one should know what the pH and alkalinity is of your soil mix is before planting in it,
and correct it if necessary BEFORE planting and before one gets it in trouble.
Exactly because Soil naturally buffers the pH, if your soil mix is right to begin with and the nutes you add are right you will never have a soil ph problem.
^Slanty
Active Member
Sorry that I overlooked supplying that info..... I was assuming that they had a good stable medium prior to planting.
iblazetoomuch
Active Member
Er one thing I didn't think of D: tnx
cary schellie
Active Member
I just got some CALi/MAGic by general hydrophonics, how often should I use in veg/flower, anyone know?