DWC Acidic PH spikes!!! Why?

[Smoakitup]

Hey guys I am growing a Purple Urkel x Trainwreck from Reserva Prevada. I have seen it grown successfully in DWC. The plant looks about average for a Pwreck.
They are some what of a Primadonna. They can't take much nutes and they really don't grow very fast in veg. I have been having a recurring problem where every 24-48 hours my PH drops to somewhere in the 4.4's :worried. So I correct and then it happens again. I first noticed this about 10 days ago so I flushed after a few days. Only to find it happen again. So I decided to swap buckets under it. No improvement!

I am using Fox farm Tiger bloom, Big bloom, Open Sesame, Hygrozyme at 690 ppm (it burns @ 800ish at this stage-Primadonna). I have heard that Fox Farm is prone to Ph spikes but usually its the other way toward the alkaline side.

I am sick of adding like 10 ml of Ph up everyday....help?

 

[xX Kid Twist Xx]

do your ppms rise when your ph drops? if so you are feeding to heavy still

 

[Smoakitup]

No they go down daily but they don't go down much when I don't closely monitor the PH. It isn't drinking much water tho...But I have been told the Pwrecks do that early in flower.

Also I forgot to mention a few key variables...
I run CO2 at roughly 900 PPM
room temp it 80
Res temp is 69-70 it varies on my Bluelab
Current ppm is 530 roughly 3 days after a flush
Rel. Humidity 40%

 

[Smoakitup]

Sorry I miss typed there the res is pretty cool actually(70 ish)

 

[xX Kid Twist Xx]

there is another post here about hygrozyme dropping ph, ill see if i can find it.silica blast is a good ph up

 

[Smoakitup]

Okay so I found the thread about hygrozyme...



I am gonna change res today...Dropping the hygrozyme, anyone have thoughts about House and Gardens MultiZen? I have been told they perform similar roles, is this true?

 

[RICHSCOTT68]

Theyre heavy feeders so your nutes are getting used faster than your use to just keep adding and stay aware of your plants intake of nutes. Think of them like teenage boys right now eat eat eat you know?

 

[TrichromeFan]

how does your res and your roots smell?

 

[tandemcarlos]

If your Airpump is in the room with the CO2 then you are making Carbonic Acid in you tanks.

 

[Aqua Man]

If your Airpump is in the room with the CO2 then you are making Carbonic Acid in you tanks.

This is a 9 yr old thread. You are right however if you have adequate buffering the effect would be minimal unless reaching extremely high concentrations. I have used CO2 in water for years and it's not easily achieved to get a 1.0 ph drop. I can't remember the numbers exactly but at about 400 ppm atmospheric CO2 depending on altitude. You will have about 3-4 ppm of carbonic acid with dkh of 4. Now the ph change will be determined by the KH of the water and the increase in CO2 ppm. CO2 needs pressure and dwell time to dissolve and agitation such as bubbles will keep it close to equalibrium with the atmosphere. With pure RO and no nutrients you can see some decent swings but that not the conditions we grow in. Generally speaking CO2 while may make a small impact on ph will not be a major factor in terms of ph in our grows because of the generally higher KH we use.