No matter what I do the ph in my 1 DWC rez is 6.3

Meast21

Well-Known Member
Title says it all and this never happened to me before. I've underfeed the plant or overfeed the plant a little in DWC and the rez is stuck at 6.3ph. I will use ph down to get it to 5.5-5.8 range and the next day its up to 6.3 again. What's going on?? On day 18 of flower, its been doing this since day 1 of flower.
 
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Billy the Mountain

Well-Known Member
Title says it all and this never happened to me before. I've underfeed the plant or overfeed the plant a little in DWC and the rez is stuck at 6.3ph. I will use ph down to get it to 5.5-5.8 range and the next day its up to 6.3 again. What's going on?? On day 18 of flower, its been doing this since day 1 of flower.
So long as the pH is in the range of ~5.8-6.3, nothing to worry about.
Rising pH in dwc is not uncommon, the rate is affected by the size of the reservoir.
 

Kassiopeija

Well-Known Member
So long as the pH is in the range of ~5.8-6.3, nothing to worry about.
Rising pH in dwc is not uncommon, the rate is affected by the size of the reservoir.
wouldnt it be possible to introduce some pH-stabilisators. aren't there products for that? like some nutes that have these special compounds in them...? that would be a helpfull additive for DWC etc
 

rootforme

Well-Known Member
My experience is that as the plant consumes nutrients it will change the ph. Are your plants also drinking a lot of water?
 

Meast21

Well-Known Member
3 small plants drinking maybe 1.5 gallons a day total... I know about rising ph in dwc, I've been doing this for 9 years... The problem is I use ph down and set it to 5.5 range and the next day its 6.3. Been doing this for 5 days now and in that time the ppm has went from 825 to 925 bc I have not been adding any water back.
 

Billy the Mountain

Well-Known Member
3 small plants drinking maybe 1.5 gallons a day total... I know about rising ph in dwc, I've been doing this for 9 years... The problem is I use ph down and set it to 5.5 range and the next day its 6.3. Been doing this for 5 days now and in that time the ppm has went from 825 to 925 bc I have not been adding any water back.
EC should be stable or slightly falling in dwc; rising ec = plant drinking faster than eating
Maybe lower your EC a bit to see the effect on pH drift?
 

Meast21

Well-Known Member
EC should be stable or slightly falling in dwc; rising ec = plant drinking faster than eating
Maybe lower your EC a bit to see the effect on pH drift?
The strain usually likes to feed at 850 ppm (tap water is 160). The ppm went from 825 to 925 and the ph would be 6.3 and then I would lower it to 5.5 and next day 6.3. It has done this now for a few days and has done this since day 1 of flower and plants are on day 18 now... This has never happend before. It seems like I could set ph to 5.0 and the next day it would be 6.3.
 

J232

Well-Known Member
You prob stuck your stink finger in the res, you have peroxide? I would lower ec and hit it with peroxide, who cares what the plants usually like, sounds like it’s not working the way it is. If the res is old, I would dump and fill, peroxide, lower ec.
 

Bucsfan80

Well-Known Member
Maybe air stone is causing it to drift up faster than normal? Idk but 6.3 isn't bad for flower in my experience. In veg mine stays 5.5 5.9 but when I switch to bloom nutes it's like 6.1 to 6.4
 

amneziaHaze

Well-Known Member
when i have baby plant ph goes up 0.2 daily when roots fill the whole bucket then its goes faster but i refil faster soo its not a big deal
 

Meast21

Well-Known Member
when i have baby plant ph goes up 0.2 daily when roots fill the whole bucket then its goes faster but i refil faster soo its not a big deal
Like I said I've never in 9 years seen plants or my rez stuck at 6.3 ph or another number.. I just lowered ph to 5.0 and put UC Roots in it.
 

Meast21

Well-Known Member
Maybe air stone is causing it to drift up faster than normal? Idk but 6.3 isn't bad for flower in my experience. In veg mine stays 5.5 5.9 but when I switch to bloom nutes it's like 6.1 to 6.4
U run DWC?? I thought 5.8 was the sweet spot?? I like mine to fluctuate from 5.7 to 6.1 though or it just seems to be in the range by itself bc when I do a rez change I set the ph to around 5.1and it rises naturally.
 

Bucsfan80

Well-Known Member
U run DWC?? I thought 5.8 was the sweet spot?? I like mine to fluctuate from 5.7 to 6.1 though or it just seems to be in the range by itself bc when I do a rez change I set the ph to around 5.1and it rises naturally.
Yeah I have a single 5gal dwc I use for youngins and I set at 5.5 and let it drift to 6ish b4 I down it. I have an rdwc that I put them in and when in flower they seem to like it higher
 

sativuuh

Member
What temps are the rest water at towards end of lights on time? The more I have to adjust ph in the 5gal, the more unstable it gets over days if you have to really fix a swing. Make sure it's cool, and I'd probably do a full water swap to be sure with fresh nuted water. Since your ph has been rising, let it mix and stablize on the lower side so your daily addbacks will naturally drift the ph back down by volume vs having to add ph down. If you are doing round buckets and the plants get thirsty, you can get black 7 gallon buckets that are just a little deeper with the same top. That extra 2 gallons of water in there really helps stabilize things.
What nutes are you using? Some certainly make ph swing more as do certain addins.
 

myke

Well-Known Member
Add some pH up,like a few ml.Your ph will stay down longer, at least for me it did.I ran about 30g.
 

Meast21

Well-Known Member
What temps are the rest water at towards end of lights on time? The more I have to adjust ph in the 5gal, the more unstable it gets over days if you have to really fix a swing. Make sure it's cool, and I'd probably do a full water swap to be sure with fresh nuted water. Since your ph has been rising, let it mix and stablize on the lower side so your daily addbacks will naturally drift the ph back down by volume vs having to add ph down. If you are doing round buckets and the plants get thirsty, you can get black 7 gallon buckets that are just a little deeper with the same top. That extra 2 gallons of water in there really helps stabilize things.
What nutes are you using? Some certainly make ph swing more as do certain addins.
Technaflora and temps are mid to high 60's... I've been doing this for a decade and never have had ph problems. I have 5 other rez's in different tents and this is the only one.
 
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