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Dreadscale
03-17-2008, 02:32 PM
Hi All

I'm am using Fox Farm Nutrients at 1/2 their recommended dosage.
I have no problems with the PH until I add the Open Sesame.
This tend to turn the whole mix in to straight up ACID. PH 4.0 or Lower.

I am using a General Hydroponics test kit, and am having to use a large amount of PH up to get it to 6.0 or better.
The PH up contains potassium carbonate and potassium silicate.

Should I use some dolomite or something ,to up the ph instead of overdosing the potassium?

I just want to stop a problem before it happens.

Thanks

Mr. Clandestine
03-17-2008, 04:31 PM
I'd go with the dolomite if your growing in soil. When you go to buy it, make sure you're not getting hydrated lime... that stuff can be overpowering and easy to add too much. (Had to find that out the hard way... :() I don't know how you'd go about diluting it, I always added it to the soil. Maybe someone else can chime in with a recommendation, or you could probably just do a search for "Lime, pH" and get plenty of good info. Also, don't spike the pH too much all at once, but raise it gradually instead. I know sudden pH fluctuations can actually shock the plant.

grey1223
03-18-2008, 03:41 PM
I don't know what medium you're using but 1/2 strength Fox Farm nutes plus Open Sesame should not drop your PH that far. Are you using more than 1/4 tsp of the Open Sesame?

Dreadscale
03-18-2008, 08:05 PM
Thanks for the input guys.

I agree with you grey1223. It doesnt seem Open Sesame should drop it that far.

I am using Fox Farm, Ocean Forest to grow in. I am testing the PH of the neutrient solution after it is mixed together. I am unsure of the soil ph at the moment but am going to check it.

I did a little test of just the Open Sesame, and alone it seems managable.

Test photos are - Plain tap water, 1/8 tsp Open Sesame, 1/4 tsp Open Sesame.

Going to do this again with all parts of the mix, later on, got to go to work now.

Thanks Again for the Input

stinkyattic
03-18-2008, 08:16 PM
Can you increase intensity of the color in your liquid tester? Add another drop... that actually doesn't look read to me; it looks more orange but get the intensity up so we can get a better look- closer up, if possible.

Dreadscale
03-19-2008, 06:08 AM
stinkyattic your correct.

It's about 5.0, Orange. Will add the Tiger Bloom and Big Bloom
tomorrow to see if it goes RED.

I was thinking the ph was good on the mix til I added the Open Sesame, but I could be mistaken.

Thanks For The Input All
:hippy:

grey1223
03-19-2008, 03:41 PM
Hang in there and keep checking and experimenting. I use ProMix HP which is peat based and it does lower the ph in the medium a little. I've also used Ocean Forest but can't remember how much it affected the ph. If you can check the ph of your runoff that would be very helpful.

stinkyattic
03-19-2008, 03:44 PM
grey, how long do you find that your promix lasts before you notice a drop in pH vs. what it was when the stuff was fresh? I find that it's pretty much good to go for the first 6 weeks with no hassles, but will start to creep down and makes it out of range after a couple months.

Dreadscale
03-19-2008, 08:12 PM
Hi Again !!

Well I couldn't reproduce my first results, I must have messed up the mix or something.

With all the ingredients added the ph is right at 5.0.
It took 1 1/8 tsp of ph up to get to between 6.0-6.5.

I am getting some Cal/Mag for my problems will see what the added ingredient does to ph.

Thanks all for the great input, it's much needed.

pix
added 1tsp Tiger Bloom-1/2Tbl Big Bloom-1 1/8tsp PH up

grey1223
03-19-2008, 08:36 PM
I hate those water testers. My eyes can't reconcile the color I'm seeing vs what my ph meter indicated. I like to keep one around just for validation of my ph meter but I'm not good at reading it.

grey1223
03-19-2008, 08:54 PM
grey, how long do you find that your promix lasts before you notice a drop in pH vs. what it was when the stuff was fresh? I find that it's pretty much good to go for the first 6 weeks with no hassles, but will start to creep down and makes it out of range after a couple months.

This may sound like a really crappy answer but I didn't use to check soil ph as I didn't normally have a problem. But when problems appeared this cycle I finally got around to checking it after it was 5 weeks into flower and it was coming out .6 or .7 below what it went in. In at 6.5 or 6.4 and now runoff is 5.8.

Well, 5.8 woun't hack it with a soiless medium as anything below 6.5 and you start locking out it would appear. It's too late for this crop, but when I watered last time I ran 7.0 water with about 150% runoff. Next time I feed I'll check again. WHOOPS, I won't be feeding these ladies again, but when I water again I'll check runoff ph. (If I water again). I'm watering less often as these are not the best ladies I've produced. They are now at 45 days and about done (Cheese). I won't know the impact of my problems until I measure yield but I've found many times they look worse than they are and yield sometimes suprises me.

So, 28 days veg, 45 days flower means they've been in the ProMix 73 days. I also noticed my mom's had 5.8 runoff last time I checked. One of them has been in a 2 gal container for several months so I suspect a salt build up. Interesting note: As an experiment I'm keeping the moms in the 2 gal pot to see how long I can keep it going before having to transfer. The last time I thought I had to transplant I ran some clearex through them and they recovered. NEW GROWERS: Please don't think you don't have to transplant THIS IS JUST AN EXPERIMENT.

stinkyattic
03-20-2008, 11:46 PM
That's very interesting. Thanks.
I've kept moms in pots way too long as well but in the past have always used a humus + perlite medium that is more pH stable than promix over time. I just went to promix myself (easier to find in winter around here) and am just WAITING for the inevitable pH drift to become noticeable. I'm trying to limit residence time in each pot to 6 weeks max now.

grey1223
03-21-2008, 08:21 PM
Stinky: The reason I use the ProMix is because the big commercial grows usually use it. To me that's a good endorsement. I will be monitoring this next cycle closely and keep log of runoff ph. Also I'll be trying a new bloom formula for part of my garden next cycle. Trying the DutchMaster Gold series. According a one long time grower in my area he claims his best yield yet last time using it. I'm not abandoning Fox Farm, just doing a comparison.

Perhaps you may have noticed that Fox Farm is drawing a line through their Ca content of the TigerBloom. I guess they're acknowledging a calcium shortage???? interesting

stinkyattic
03-22-2008, 12:31 PM
I haven't touched fox farms in a while- the grow big would form a precipitate at the bottom of the bottle pretty quickly and I didn't trust it once I heard salt crystals rattling around in there.
I'll be interested to see what your runoff pH looks like over time.