pH rising 0.2 per day, but ppm staying the same...

[maryjanesjungle]

Why would this accrue?
Here are my setting and growing conditions:

35gal DWC
400W HPS on 12/12 from seed
ppm at 340
pH 5.8 now (was 5.6 yesterday, and 5.4 the day before that)
temps are 79-85F 9" below light (is this too close?)
res temp is 69-72 (using a water cooler to achieve this)

 

[maryjanesjungle]

up another .15 to 5.95 today, yet my ppms are still around 340... no one can tell me why this is happening??

 

[abuldur]

what kind of nutes are you using ?
ph fluctuation is ok as long as it stays between 5.5 and 6.5.

peace

 

[maryjanesjungle]

sensi bloom part A & B
i know a lil flux is ok but its going to move out of that range in a week at the rate its going which is not good. ppm i actually up from 340 a lil but not much, maybe 350 max.

 

[yamaha_1fan]

Use some PH down


Is the hydroton new? I have heard people say they have hadd issues keeping PH stable with new hydroton

 

[stevewinthrop]

DWC is hard to stabilize pH.

Also, I'm not sure if sensi a/b is advanced nutrients, but they are notoriously terrible with pH fluctuation, and the solution they provide is to invest in some pH down. Also, if your ppms are staying the same for 3 days, something is wrong, lol... Your plants arent drinking!

I think i've also read that the evaporation caused by the bubbles popping on the surface of the water also will raise pH slightly over time... But a .6 flux in 3 days isn't that terrible, if you were running a 5 gallon or 10 gallon dwc, your pH would be all over the place all the time.

The biggest thing you need to know, is that as long as you keep it under 7.1, and above 5.1, your plants will be fine.

-- steve

 

[stevewinthrop]

Sorry, I retract the ppm statement, didn't realize your roots/plants were so tiny. But if your ppm goes UP, then cut down on nutes a bit... small plants dont need much.

-- steve

 

[maryjanesjungle]

advanced nutrients

advanced nutrients

yamaha_1fan,
No offense intended here but pH up/down is not the answer to long term stabilization, I learn that last grow. And the clay balls are not new (used them last grow) and they has been washed before use this grow also.

stevewinthrop,
Thanks for the info about sensi, i didn't know they were known for pH flux. Id like to see further proof of that before I etch it in stone but its interesting none the less. They are however advanced nutrients (whatever that means) if that link there is to be believed. What does that mean??

I've heard of people attaining stable pH levels for weeks at a time. The chart below is where I went first when I noticed my pH moving too much, but it doesn't say anything about pH rising and ppm not moving or slightly moving upward so I'm lost. The plants are obviously drinking something as the water level is going down and the plants are growing rather nicely.

I would think pH going up .2 per day and ppm staying the same if not going up a lil would mean the plants were drinking more water then nutes and thus the slight ppm rise. But more nutes in the water SHOULD cause the pH to drop not rise so again I'm lost.

 

[maryjanesjungle]

oh and by the way, i was told 340 ppm was ok for plants this size. also i used distilled (0 pH) water to start with.

 

[Brus]

What did you wash the hydroton with? Plain water?
As yamaha 1fan said the hydroton are often the cause of pH rise, atleast it was for me.

Have you used the container before?


Hope you find out whats causin the rising of the pH.

Best regards.

 

[FreezerBoy]

Wish I could help. Unfortunately, your understanding of EC/pH is the same as mine and so, my confusion is the same as yours. I've heard aeration has a tendency to raise pH but, have no evidence.

I will say with GH nutes, pH and EC stabilization is a breeze. Within a week of getting my Truncheon I was so dialed in I was locked down. EC and pH held steady for more than a month. Turned out to be a bad thing. Widespread deficiencies from pH lockout as no one # provides all nutes.

I now plan a mild swing by feeding slightly rich and alkaline. Over two weeks EC climbs and pH drops, 4 gallons of tap water brings back original readings.

 

[tex1969]

How many days has the nutrients been in the dwc tub, ie freshly mixed 2-3 days ago? Is your hydroton filled cups partially submerged in the solution? Since there is not much the plants can be doing to the nute mix at this time it has to be either the mix itself or something that is making contact with it. I am starting my first dwc grow myself. I tried maxigro/bloom and flora nova, but the ph kept climbing after being lowered with ph down. I do not know if it has something to do with the buffering agent trying to bring the solution back to a set range or not but I did not want to deal with either. I am happy to say I have settled with the lucas formula using gh micro/bloom in ro water. The ph flux is down to the .03 range and no ph adjusters needed.

 

[maryjanesjungle]

ya since the plants are so small i have had the water level touching the pots, good thinking. ill lower the level and see if the ph rise slows,.. clay balls were washed in tap water.

yesterday i dropped the ppm down to 314 and the ph to 5.49 and a lil over 12 hours later its up to 5.72

 

[tex1969]

What did you germ your seeds in, I see a coco pot onto of your rez, so I was just wondering?

 

[maryjanesjungle]

I germed all 9 in wet paper towels, then put 3 in those coco pots that u saw,....

(the black domina were in the coco and they've been giving me a bitch of a time, took 6 seeds to get 3 plants, and the last two to germ and grow are really taking there sweet ass time)


...the 3 haze X skunk 1 and the 3 kali mist all germed and grew perfectly with only usung 3 seeds for each strain. I planted these two strains in homemade cardboard containers till they were about 2 inches tall, then they went in the res. only one of the 2 black domina is really keeping u with the haze and kali mist but its early.

FYI here is a link to the diary ive been keeping:

http://www.icmag.com/ic/showthread.php?t=100616&page=2&pp=15

 

[FreezerBoy]

wrong you will allways need it making it long term

Only in Bizzaro-Land. Constantly pumping pH Up or Down into your system is a clear sign you're doing it wrong. Dialed in, you can control pH with food and water.

 

[00420]

Only in Bizzaro-Land. Constantly pumping pH Up or Down into your system is a clear sign you're doing it wrong. Dialed in, you can control pH with food and water.

i must be doing things wrong then.......

8ml floranova with r/o{7.3} = ph 6.4 hear in bizzaro my plant's tell me they don't like more nova but want less ph care to explain how to control it with food/water?

 

[FreezerBoy]

care to explain how to control it with food/water?

I feed slightly strong and alkaline. Slowly, over two weeks, EC climbs and pH drops. Four - six gallons of tap water brings all three back to their original levels.

I try to keep pH Down to those times I need a whole new res from scratch: At the beginning, the mid-grow res change and for the flush. I don't always manage but, I go weeks at a time without needing the help of pH Down.

 

[maryjanesjungle]

I've read of people being able to attain a balance and not need pH up/down. Now I'm not like completely against pH up/down or i wouldn't own them, I feel they gotta be needed sometimes or why were they invented, but if others can get a balance I just think that sounds like a better way then constantly adding pH down (which if you do to a gallon jug of distilled water raises the ppms)... If I constantly had to add pH down to stay right id think in time my plants might eat all the nutes and be left with nothing but distilled water and pH down to dine on.


My goal this grow, which is only my second so correct me if I'm wrong to think its possible, is to have my ppm drop very very slowly and in turn have pH rise very slowly. This would allow me to add a gallon jug of distilled water that I've added fertilizer and pH up/down to as the plants drink. I figured I would just monitor daily and listen to the plants. If the ppms start dropping too fast ill add more nutes because the plants would be telling me they want more nutes.

Sorry for the noob question but where does one get ro (Reverse osmosis) water? I've never heard of it till now. What are the ppms of it right out of the bottle? I chose distilled water because my friggen tap water is 450!!

I just figured going with 0 ppm made sense so i could add what I wanted. Oh and by the way to answer your question I'm using Sensi Bloom A&B ferts along with some cal/mag as last grow i had cal/mag deficiency with just Sensi.

The distilled water I've been using is 0 ppm and 6.35 pH right out of the jug. Is this ok or should I in fact switch to ro water?

 

[FreezerBoy]

Ya gotta do what ya gotta do. If that means pH Down, that's what it means. RO is homemade water. It's run thru a filter and for every 2-3 gallons you run through it, you'll get a gallon of RO. The rest drains off or is collected for other things.

I think they run in the $150-$300 range. Do some homework. They come with "stages". Some argue two is enough, others three, others four.