coco ph to high?

so my grow has been underway for 2 weeks now. when i first started out i purchased a very cheap oh meter for 10 dollars with a big stake you drive into the ground and it takes the reading. however it seemed that no matter what i stuck it into it always came up with the same reading of 7. so i figured it may be faulty. so i got a slightly better one for 30 moneys which also is a moisture meter and light meter. it is not digital, takes no batteries, and operates in the same way as my first one. with 2 long stakes that you stick in to the ground. anyway. iv got 1 of my seedlings and a couple of larger plants in a 50/50 coco/perlite mix.

the coco claims to be EC and PH balanced "for optimal growth". and i gave it a very decent wash before i started using it. anyway all my pots are measuring at about 7 or 7.2 and if i measure just the straight coco sitting in the bag it measures 7.0. is this to high?

iv started feeding a couple of plants. will nutes raise the ph or lower it?. my water is ph balanced,reserve osmosis. so im not sure the problem. is this to high and if so what measures can i take to lower it while it's got my plants in it and is potted?. cheers here's some photo's of the girls btw. this photo is 1 day old

Soil ph probes don't work very well in coco.

You can use an aquarium dropper ph test kit for your nutes.

Nutrients generally lower your water ph.

However with RO water there are very little minerals left to sustain an adaquate buffer, so most add extra Ca and Mg to compensate (150-200ppm)

If your coco is of good quality then you rinse away the buffering agent that its stabilised with before packaging when you pre-rinse it.


Personally I ph to 6.0 but every 4 weeks I reapply Ca and Mg and an EC of 1.0-1.5 depending upon stage of growth.



J

I feed a little lower ph. 5.8 but generally 5.8-6.2 is where it should be sitting in coco from all the information I've ever got. If I'm not mistaken (which I could be) Mg won't be absorbed in soiless/hydro above a ph of 5.9

See if you can buy some calibration agent for your ph meter than you will know for sure--I usually get the ph 7 to make sure my meter is dialed in

DurbanP said:

I feed a little lower ph. 5.8 but generally 5.8-6.2 is where it should be sitting in coco from all the information I've ever got. If I'm not mistaken (which I could be) Mg won't be absorbed in soiless/hydro above a ph of 5.9

See if you can buy some calibration agent for your ph meter than you will know for sure--I usually get the ph 7 to make sure my meter is dialed in

Click to expand...

From the research I've done into coco as long as the buffering agent (calcium nitrate) is still present then coco will buffer pretty well.

5.8 is optimum for coco but like you mentioned anything from 5.5-6.2 will work but could cause certain nutrients to be more available than others.

Mg can be uptaken I think from 5.7-6.5 calcium from something like 5.2-6.0 but I could be a little out.

I used to be really anal about ph adjustment, making sure everything was 5.8 on the nose.

however my BLUELAB pen needs calibrating pretty much every use and I just can't be arsed anymore so I do a dropper test.

I use SERA dropper kit. If it shows up yellow I don't adjust.


J

I was wrong. Here is a chart someone posted on here that I took a screen shot of a while back, wish I had the users name to give him the credit for posting it. Maybe this will help.

DurbanP said:

I was wrong. Here is a chart someone posted on here that I took a screen shot of a while back, wish I had the users name to give him the credit for posting it. Maybe this will help.View attachment 3284694

Click to expand...

That's a good chart. It's one I have in my albums for reference.


Like I said though coco generally buffers pretty well if you haven't washed away the precharge buffer.



J

hmmm. even sticking the prove straight into the bag of coco gives a reading of 7.0
i have a cf.c.ppm meter but to be honest i don't find measure the run off to be very helpful at all. sometimes the ec is off the meter sometimes it's at the very bottom.

my plants seem to be growing fine. i think it's the meter to be honest. il go and harass the guy at the grow shop on pay day
so nutes will make my soil PH more acidic? is this correct. or will my ph stay pretty stubborn. i really need to know if my readings are accurate before i start worrying about it. i may go to the grow shop and ask the guy there to run some tests on the shit they sell and get some accurate readings so i know the ph is legit before buying it.

cheers guys

opiumfiend said:

hmmm. even sticking the prove straight into the bag of coco gives a reading of 7.0
i have a cf.c.ppm meter but to be honest i don't find measure the run off to be very helpful at all. sometimes the ec is off the meter sometimes it's at the very bottom.

my plants seem to be growing fine. i think it's the meter to be honest. il go and harass the guy at the grow shop on pay day
so nutes will make my soil PH more acidic? is this correct. or will my ph stay pretty stubborn. i really need to know if my readings are accurate before i start worrying about it. i may go to the grow shop and ask the guy there to run some tests on the shit they sell and get some accurate readings so i know the ph is legit before buying it.

cheers guys

Click to expand...

I use a BLUELAB EC truncheon.

When I use the coco straight out of the bag it has an EC of around 1.2 tested by pouring straight water through the coco until a small amount of runoff is achieved.

I precharge with 0.8EC.

I then continue feeding at 0.8EC until the runoff is either lower in EC or plants look like they need more nutes.

Then I pretty much increase by 0.2EC each week until I hit 1.4EC in veg.

Then in flower I increase 0.2EC per week maxing out around 1.6-1.8.

If at any time my runoff EC is higher than my input EC then I back off the strength a little.


J