Register ICMag Forum Menu Features Mark Forums Read
You are viewing our:
in:
Forums > Marijuana Growing > Indoor Grows - Hydro > ph rapidly dropping ppm stays the same?

Thread Title Search
Click for great deals at MB Ferts
Post Reply
ph rapidly dropping ppm stays the same? Thread Tools
Old 05-07-2009, 09:43 PM #1
turbolaser4528
Senior Member

turbolaser4528's Avatar

Join Date: Apr 2008
Posts: 1,264
turbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the rough
ph rapidly dropping ppm stays the same?

I have been having this problem for some a good month with my 2 nycd x g13 from Soma in a 31 gallon rubbermaid, DWC gh nutes, lucas formula, 400w hps, in a wooden armoire, temps stay between 70-85 and rh is 40-60 %.

The ph just keeps dropping, I flushed with plain tap water (~130 ppm) for a good 8-10 days and the ph would just keep dropping to like 3.8-4.3. ppm would stay about the same maybe drop a little. But it didnt go up, ph never goes up in my setup. Maybe I am undernuting? I have kept the ppm at around 700-800 on a .7 conversion. I have an expensive hanna meter thats calibrated so I know my readings are pretty accurate.

I read somewhere that maybe its because I don't have enough nutes that the ph is so unstable? What fools me is that the tips of the leaves are burnt, much like nute burn, but when i flush and flush the plant doesn't dump anything major back into the res.


Sorry if this is posted in the wrong section, just don't know what to do, so frustrating. Also, both plants are almost 4 feet tall, vegged for ~30 days under a 125 500k cfl, in about week 8 of flower. Some of the leaves are starting to turn pale yellow like they are lacking nitrogen (from the flush i guess) but im scared to add nutes as they already show symtoms of nute burn (burnt tips, edges, stunted growth) maybe this is a deficiency?

any help would be appreciated, sorry for the lengthy post, and i did search a good deal.
turbolaser4528 is offline Quote


Old 05-07-2009, 10:46 PM #2
cyberwax
Guest

Posts: n/a
Are you using ro water? If so the carbon hardness of your water is probably too low as the plant exchange one part mineral for one part acid when growing alot/budding.(usually from 2 weeks into flowering and onwards)

If possible i would suggest using some parts tap water in the mix to raise the buffer, ph up usually doesnt contain any buffering, unless you get some sort of ph+/kh+ additive. I know some aquarium stores sell em. But as said the easiest way is to just add some parts tapwater and rest ro, if tapwater is useless for the purpose then i would suggest either ph+/kh+ or just find some gh or kh salt.
Quote


Old 05-07-2009, 10:50 PM #3
10k
burnt out og'er

Join Date: Feb 2006
Location: cyber space
Posts: 1,644
10k is a jewel in the rough10k is a jewel in the rough10k is a jewel in the rough10k is a jewel in the rough10k is a jewel in the rough10k is a jewel in the rough10k is a jewel in the rough10k is a jewel in the rough
Are you using GH Flora micro for hard water ? If so...that's the problem !

The micro for hard water you need to premix in a holding drum and wait a couple days to see if you need to pH it, otherwise if you pH it the day you mixed it, it will not hold that pH worth a damn, instead it will drop way out of range like an anvil over the next day or two. Or better yet, get rid of the hard water micro and get the regular GH flora micro.

Here's what Lucas had to say about it...
Quote:
One tip - do not pH down this stuff, the hard water micro will drop pH gradually over the next 24 hours, for example I mix up a batch, it is at like 6.2, the next day, its at 5.6-5.8 after running in the system for a while. If I pH downed that to 5.7 before putting it in the system, it ended up as low as 4.8-5.2 by the next day. My conclusion, the hard water micro was buffering the alkaline crud in my water, it just does not do it ASAP fast like the phosphoric acid.
hth,
10k
10k is offline Quote


Old 05-07-2009, 10:50 PM #4
Blunt_69
the keeper of the creeper

Blunt_69's Avatar

Join Date: Feb 2006
Location: NA somewhere
Posts: 1,431
Blunt_69 is a jewel in the roughBlunt_69 is a jewel in the roughBlunt_69 is a jewel in the roughBlunt_69 is a jewel in the roughBlunt_69 is a jewel in the roughBlunt_69 is a jewel in the roughBlunt_69 is a jewel in the rough
Nothing describes it like a picture. Lets see it..

I would try some RO water if your city water ppm is that high, it may be effecting your PH. Generally with lucase your PH sits 5.8 to 6.0.. If it is dropping means there is to much Nutrients, your girls are uptaking more water. Try a lighter mixture of 5 micro 10 bloom per gallon.dont adjust the ppm just run with it. .5 conversion should be around 600ppm
Blunt_69 is offline Quote


Old 05-07-2009, 10:52 PM #5
Hydro-Soil
Banned

Join Date: Aug 2008
Location: 10K feet above sea level... awesome!
Posts: 7,263
Hydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud of
Two things will drop pH fast in DWC, root rot from res temps over 68F and root rot from not enough dissolved oxygen.

You should have at least 1 watt of airpump power per gallon of water.

Keep your res temp as close to 65F as possible and between 65F and 68F. With additional oxygen you can go with higher res temps but the noise is increased as well.

If you live in an area where it gets to 90F and above, you would probably save yourself a lot of headaches, time and money if you switched to drip or E&F. (Edit: I've used DWC/SWC for years in desert environments and finally switched. Sweeeeet Relief!)
Hydro-Soil is offline Quote


Old 05-08-2009, 03:00 AM #6
turbolaser4528
Senior Member

turbolaser4528's Avatar

Join Date: Apr 2008
Posts: 1,264
turbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the rough
thanks for the help guys, I am using gh hardwater micro mixed with the regular micro. I will stop using the hardwater micro, and that should help keep my ph stable right?

Res temps never get above 74*F usually they are at about 68-69*F and I am using a silent air x5 air pump (its only 6 watts YIKES!) BUT my roots are healthy as can be, no root rot they are nice and white and clean, and i have a 450 gph pump on a digital timer to keep the 31 gallon res churning (4 mins on, 10 off)


I am not using RO, like i said its tap and its ~130ppm.

I dont have a camera otherwise I would post pics, also I am on a .7 conversion with my meter, what the 5/10 ratio equate to ppm wise? ~900?


Right now I checked my res and the ppm stayed at 800 but the ph dropped from 5.81 to 5.57 since this morning. HOWEVER, I did add 35 ml of hardwater micro and 70 ml of gh bloom, maybe that caused the ppm drop?


Thanks for the help, i will only use the regular gh micro, and keep you all updated. Id post pics if I could.
turbolaser4528 is offline Quote


Old 05-13-2009, 04:51 AM #7
turbolaser4528
Senior Member

turbolaser4528's Avatar

Join Date: Apr 2008
Posts: 1,264
turbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the roughturbolaser4528 is a jewel in the rough
UPDATE: Ok guy so my veg bubble bucket is staying rock steady with a ph of 6.09 and a ppm of ~900. Plants are 2 white widow x indica bagseed crosses in about day 30 of veg, in a small 3 gallon dwc.

So the lucas formula is working well for me now, I was undernuting them and that was my problem, bumped it up to 900 and they look very healthy.

The main plants in the flowering chamber, the ph is falling about .6 each day, and the ppm is rising about 30 each day. Is this within reason?

It seems with a ppm of 1080 it was too strong for them which is reasonable, 950 or so seems like it would suit them better, i shall give them that for their final week or so of flowering.


Thanks for your guidance everyone I can't wait to throw some harvest pics up here, and yiled huge on my next batch now that I know what I'm doing better!!!!!
turbolaser4528 is offline Quote


Old 05-13-2009, 06:14 AM #8
Hydro-Soil
Banned

Join Date: Aug 2008
Location: 10K feet above sea level... awesome!
Posts: 7,263
Hydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud ofHydro-Soil has much to be proud of
Quote:
Originally Posted by turbolaser4528 View Post

The main plants in the flowering chamber, the ph is falling about .6 each day, and the ppm is rising about 30 each day. Is this within reason?
Yes... You're going to see it swing a bit but nothing out of normal ranges.

Just top off with RO water and bump the ppm back to 900-950 about once a week and you're solid.
Hydro-Soil is offline Quote


Old 05-16-2009, 05:39 PM #9
JohnnyToke
fourtwentytwentyfourseven

JohnnyToke's Avatar

Join Date: Aug 2007
Location: Rockridge
Posts: 453
JohnnyToke will become famous soon enoughJohnnyToke will become famous soon enough
[quote=turbolaser4528;2331438]

I am not using RO, like i said its tap and its ~130ppm.
QUOTE]

If your tap is only 130ppms, I would recommend using regular micro instead of the hardwater version. If your tap is 300+ ppms, then I would recommend the hardwater version.

JT
JohnnyToke is offline Quote


Old 05-16-2009, 07:09 PM #10
Standaman
Member

Standaman's Avatar

Join Date: Mar 2009
Location: Wild West Midlands UK
Posts: 511
Standaman will become famous soon enoughStandaman will become famous soon enough
Hey hydro-Soil i just read what you said about Res temps mine are up i have got them down a bit today by swapping my airstones there are two per pot and lots of bubbles now

My air pump is a 10w/10L per min. Should i go bigger to compensate?

Thanks
Standaman is offline Quote


Post Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT +2. The time now is 08:25 PM.


Click to Visit Mile High Glass Pipes!


This site is for educational and entertainment purposes only.
You must be of legal age to view ICmag and participate here.
All postings are the responsibility of their authors.
Powered by: vBulletin Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.