5 Gal DWC pH Problem

danneede

Member
5 gal bubble buckets with large blackberrys just started 12/12
dyna gro nutes + pro tekt
200 ppm tap water + 200 ppm nutes = 400 ppm (I know thats low, trying to get the pH right before i add more)
pH rapidly drops from 5.6 -5.8 to 4.4 4.6 over 24 hours
ppms also drop along with water level
res temps 65-67 and completly dark with plenty of o2 from 45L/min air pump
plants are ok and growing fast however showing some def
Pic from last grow, just something to make this worth your while thanks
344.jpg
 

Uncultivated

Well-Known Member
let your water sit for 24 hours before using it to burn off chlorine and maybe whatever else is ailing it.

I presume you have a ph control kit? If not get one right away $17 on Amazon.
 

danneede

Member
yea thats how i adjust my ph. the problem is it flucuates after i adjust it. everyday i put it back up to the 5.5-6.0 range. the water should have already burned off the chlorine i would think that would only be a problem after a res change.

I was thinking maybe i should add more nutes as that might help buffer the water, not sure though.
 

cruzer101

Well-Known Member
I would bring the pH up to 6.2 and don't let the temps exceed 72° in the water. Give it a day or two and it should settle down. Maybe pick up some cal mag.
 

danneede

Member
I would bring the pH up to 6.2 and don't let the temps exceed 72° in the water. Give it a day or two and it should settle down. Maybe pick up some cal mag.
Res temps have never been above 68. I'm goin to try bringing the ph up high and see how it responds. Probably to about 6.2- 6.5 like you said. Will the cal ma help stabilize the water? I got mag pro will that help?
 

danneede

Member
then i dont know unless there might be buildup of nute salts on something. when you add nutes do you have to adjust the ph up?
Yeah i have to adjust the ph up everyday this last week even when i dont add nutes. I was thinking maybe i just need a res change but the water looks so clear it doesnt seem like it could be the problem.
 

cruzer101

Well-Known Member
Res temps have never been above 68. I'm goin to try bringing the ph up high and see how it responds. Probably to about 6.2- 6.5 like you said. Will the cal ma help stabilize the water? I got mag pro will that help?
I had suggested the cal mag because you mentioned you are starting to see minor def and most of the time thats what's needed. It will affect the ph like your nutes do. I suggested rising the pH for a couple reasons, One is plants in flower absorb more of the nutrients they need at that pH and the swing if it continues will still be within acceptable levels. I doubt its a salt build up I'm pretty sure that would increase pH. You nutrients are probably pH balanced so they will lower the pH what you are using to raise the pH maybe bad (try baking soda) or you got something in the water that's doing it. Are the roots slimy?
You could always get another 5 gallon bucket, fill it with the same nutes as your DWC and monitor the pH in it along side it to find out.
 

haole420

Active Member
i was using only RO water, but started mixing 200ppm tap water with RO water 50/50 to add in some calmag. i did notice my pH fluctuating (upward) more. google "unstable ph tap water CO2." there are a few articles out there saying how dissolved CO2 in pressurized tap water can cause fluctuations in pH. recommendation is to aerate the water thoroughly for 24hrs (or until you get a stable pH), then add nutes, and pH up or down. maybe add in some RO water from wolly world or elsewhere.
 

Uncultivated

Well-Known Member
Ive never had any problems with my meter in the past. Even when i calibrate its never more then .1 off, if that.
If you calibrate and you have the storage solution, then yeah it'll be good assuming its a good meter. If you just bought a cheap meter with no calibration or storage solutions, it can be less than reliable. I was thinking about getting one, but then I realized how much I'd have to spend and figured I was better off with my $17 ph kit after all.
 

danneede

Member
I had suggested the cal mag because you mentioned you are starting to see minor def and most of the time thats what's needed. It will affect the ph like your nutes do. I suggested rising the pH for a couple reasons, One is plants in flower absorb more of the nutrients they need at that pH and the swing if it continues will still be within acceptable levels. I doubt its a salt build up I'm pretty sure that would increase pH. You nutrients are probably pH balanced so they will lower the pH what you are using to raise the pH maybe bad (try baking soda) or you got something in the water that's doing it. Are the roots slimy?
You could always get another 5 gallon bucket, fill it with the same nutes as your DWC and monitor the pH in it along side it to find out.
Yea im trying to not add any more nute until i get the pH thing figured out thats why there starting to get a little def. I use GH pH up and down. the roots look great no slime and there bright white. the plants look pretty healthy and are still growing very fast.
 

danneede

Member
i was using only RO water, but started mixing 200ppm tap water with RO water 50/50 to add in some calmag. i did notice my pH fluctuating (upward) more. google "unstable ph tap water CO2." there are a few articles out there saying how dissolved CO2 in pressurized tap water can cause fluctuations in pH. recommendation is to aerate the water thoroughly for 24hrs (or until you get a stable pH), then add nutes, and pH up or down. maybe add in some RO water from wolly world or elsewhere.
The first week the pH was stable then it started going crazy. So i dont think its the tap water as if it was i think the problems would be getting better not worse over time. Im goin to change out the water in the buckets anyway, hopefully that will solve my problems. I have been waiting to buy a little pump to pump out the buckets but i can't wait any more im just going to put the plants in different 5 gal buckets while i change the water in there current buckets.

One concern i was having is the tap water is cold, probably about 50 degress if that when it comes out. Will that harm my plants until it warms up in the room to 65 where it generally stays. Warming up the water will make the task more time comsuming so if i can get away with out doing so that would be good.
 

danneede

Member
If you calibrate and you have the storage solution, then yeah it'll be good assuming its a good meter. If you just bought a cheap meter with no calibration or storage solutions, it can be less than reliable. I was thinking about getting one, but then I realized how much I'd have to spend and figured I was better off with my $17 ph kit after all.
I really like my meter. I got the water proof hannah and it was kind of expensive. However, it is accurate and gives me fast readings. i calibrate it regulary(most of the time i dont even think its nescesary) and keep it in 7.0 storage solution. Can you reusue the strips or do you have to buy more?
 
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