Rapidly dropping pH levels in bubbler! What to do?

[Mr. Bobby]

Hello all you ganja lovers. This is my first post here

I've been growing for about half a year (got my third generation in veg right now) and I thought I had a pretty good idea of how things are working with these babies. Just the other day I decided to get a decent digital pH and EC meter. I have noticed that pH levels are dropping rapidly for some of my plants.

I have all my plants in different 10-liter buckets with airstones at the bottom. A basic bubbler setup. The babies have been flowering for a little over 4 weeks. I just changed water the other day in the bubblers and everything was pretty good on the money pH and EC wise 6.4 - 6.9. However I've noticed that pH as been dropping to even as low as 4.6 in just three days!! EC levels have stayed more or less the same. My vegging babies do not show this kind of pH dropping. The plants look good to me (no signs of nutrient deficiencies).

So basicly i'm wondering: first of all is this normal? And second, what should I do? I've been trying to add some pH up but the levels are dropping so fast I can't keep with it and I don't think this can be healthy for the babies.

Any comments? Please help me out here! Google doesn't have any answers :-/

Thanks!!

EDIT: Found this post http://www.icmag.com/ic/showthread.php?t=121031 which was very interesting, talking about GHE's Micro for hard water being the source of the problem. I do use GHE but my nutrient bottle says it's for soft water. Could it still be the source of the problem?

 

[lakerschamps09]

I have the same problem with my plants 4 weeks in flower too i read something that said if the plants are eating alot of food the ph drops?Idk maybe someone will come in and help i need to know too

 

[cyberwax]

There have been a many a post about this and the solution is to get a bigger res. As the plants start to get big and grow alot they exchange one part mineral for one part acid, leaving you with the acid in the tank. With such a small(10 liter) res, you should expect a drop like this.

 

[lakerschamps09]

does this lockout any nutes?

 

[cyberwax]

Most certainly, but not directly from the res size; but as you already know ph that drifts beyond recommended lvl locks out nutes, wich in turn is an effect of the reservoir size. This change also occur with giant reservoirs but as the time it takes is proportional to the size it takes alot longer to affect the water.

So yes.

 

[FreezerBoy]

pH and EC wise 6.4 - 6.9. However I've noticed that pH as been dropping to even as low as 4.6 in just three days!! EC levels have stayed more or less the same.

The smaller the res, the faster the disaster. Your 10 liter bucket is lucky to hold 6 liters of water after allowing for airgap. I'd suspect you have to adjust things several times a day. By comparison I use a 68 liter tub with 45 liters of water for a single plant. I adjust things every other week.

Proper pH levels for DWC are 5.6-6.0.

You say EC is moving . Which way?

What's the EC of your water?

 

[medi-useA]

The smaller the res, the faster the disaster. Your 10 liter bucket is lucky to hold 6 liters of water after allowing for airgap. I'd suspect you have to adjust things several times a day. By comparison I use a 68 liter tub with 45 liters of water for a single plant. I adjust things every other week.

Proper pH levels for DWC are 5.6-6.0.

You say EC is moving . Which way?

What's the EC of your water?

Mr. Bobby-> I have a single plant in an 80Ltr tub DWC with one 3" disk-like airstone...My last grow was DWC in a 20Ltr bucket....I had the same ph probs @about the same time in flowering....I found by setting ph to 5.0 the 'drift-timeline' was extended without 'knocking' the plants growth. @ this time in the cycle, a ph of 5.0 is quickly overcome...@least, th@ is my experience with my last {and first!} DWC grow...am on my second one as I type...
I upgraded from the 20L bucket to an 80L black plastic tub....I put 2 holes for baskets in the tub lid, evenly spaced...I only use one of the holes for the netpot and plant...the other is an access port for inspections, tests and nut top up!
Lifting the bucket lid with flowering plant every day for testing and topup is a PITA! The tub uses space much more effectively, Holds a lot more nutes and has ample space for rootgrowth-fine, hairy root growth!


I would aim to get a black plastic tub with lid th@ fits your growspace as soon as possible.


muA

ps....keep an eye on the ph!...in my gallery are pics of my harvested buds...you can see the brown, damaged 'trim' leaves th@ went soft and brown because of the nute swing!...even some of the buds were affected!..keep an eye on the ph!

muA

 

[lakerschamps09]

so adding more base solution to drop the ph would be counter productive huh since its adding more salt causing the nute lockout?besides getting a bigger tub which aint a option right now (no space) what else can i do besides whats mentioned above??

 

[cyberwax]

Grow in soil or use another hydro system, or just simple maintain ph every day, perhaps twice a day.

And yes, adding more nutes is actually counter productive but its also something you have to maintain, its the way of the plants. They need nutrients but they also need the correct ph, stop being lazy or stop growing.

 

[Kindman69]

You'll have to adjust 2+ times daily and make sure you are topped off.

 

[RewTheJew]

How are your rez temps? I hear a major drop off in PH is a good sign that root rot is in your future. Just a thought