Ph Problems, please help a new grower!

Hey guys, this is my first time ever trying to grow. I am using a top feed DWC “bubbleponics” hydro method. My 2 Northern Lights and 2 Gold Leaf seeds sprouted on March 6 and I moved them into my 3x3x6’ tent that night. The first week I used straight pH water that was somewhere in the 5.5-6 range. My 4 plants (all sharing 1 reservoir for now) grew great the first week, maybe there was a little stretch until I lowered and increased the power on my 600w MH light.

I replaced the water in the reservoir on on 3/13 and added the first nutrients (about a 1/4 tsp of General Hydroponics trio per gallon of water for a total of 5 gallons). On 3/11 I had to turn the lights off in the tent for about 5 hours. On 3/14 the lights were off for 10.5 hours!

I now realized that since replacing the water in the reservoir, my pH has been around 7+. Last night I tried to remedy that, but today they spent the day in a ph of under 5.

Please take a look at the attached photos and let me know what you guys think is the main problem. 1st GL has brown spots in middle of leaf. 2nd GL seems to be slightly dark. 1st NL looks like its about to die, but its been a bad plant from the beginning so I never had high hopes. The 2nd NL appears to be twisting on the sides. All the plants appear soft and are droopy compared to before. Lights are at 100% at about 31" away at the moment so I doubt it is light burn of any kind. I am guessing my royal ph !@#$up is what caused the damage? Temps are steady around 77 f and rH in high 40s. I have stabilized the pH this evening. Should I go ahead and flush the reservoir again? Should I give the plants plain pH water? Will they recover? Any forensics and advice would be most appreciated!

Your ph for hydro plant should be 5.3-5.8, 5.5 potentially being the best for hydro hope this helps

You have to stop the wild pH swings, keep it steady even if you have to check it everyday until you get the hang of it.

You have to stop the wild swings in the light cycle too, one of these issues is bad, but the two together you could lose your garden -good luck


Nicely explained @Paranorman

Thanks @Paranorman for the tip. My lights were off those times due to my landlord fixing up my apartment. They should be consistent from here on out. I have from time to time turned my lights and fan off for 30 min or so to increase humidity in my tent. (My fan is a bit too powerful and sucks out a lot of humidity but I don’t want to splurge on a vsd to lower it’s speed and I need it on full to control heat). Are these short random turn light turn offs a bad idea?

I think I figured out the main ph issue though. I am using one of those liquid ph indicators that changes color depending on the pH to test my water. Well my general hydroponics nutes have colors of their own (pink, brown, and green) that seem to be altering the color of the pH indicator. I probably tried for 3 hours straight to get my ph in the right range yesterday but a single droplet of acid/base would fluctuate the pH from 4-8. I replaced the reservoir with plain pH water for now (it was ez to get the ph right with no nutes) until my digital pH monitor arrives. The plants seem to be slightly better off today.

I know the products. I do not believe their colors are related to your pH issues. pH is related to the acidity or alkalinity of your water.

Right, but I am unable to adjust my pH into the acceptable 5.5-6 range with nutes added. I even was putting a single acid drop on a spoon wiping 90% of it off and mixing in the rest and it would cause my reservoir to go from a pH of around 6.5 to 4. I tried letting the reservoir sit for 30 mins between testing, I tried everything it seems. I am obviously doing something wrong with the nutes/pH. I followed the nutes instructions and never mixed undiluted nutes. The only thing I could think of was that the dyes/coloring in the nutes were slightly changing the colors of my pH indicator so I wasn’t getting an accurate reading. It could also be the way I’m.mixing in my nutes? Not sure

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It does sound like something’s wrong and I’m just not quite understanding it.

I’m sure somebody else here can help you, I used to grow Hydroponics and I honestly have never heard of what you’re saying, but that’s just me …and I didn’t use that particular brand of neut so…

Edit: I would fill my reservoir, add however much nutes the bottle recommended* then I would test my pH and let’s say example it was 7.0, I would lower it down to 5.8 - 6 SLOWLY, adding pH Down little by little, testing as I went…

*I seldom use half of the amount the product recommends by the way, but that’s just my personal growing style

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It is odd, but to add my two cents worth…
Add the pH drops, and wait 30 minutes, give them time to circulate and work, then retest pH.
If you test right away, it may read 5.8, but in 30 minutes, it could change up or down.

Like @Paranorman said, slowly!


Yes, all the symptoms are related to the pH swings.

Yes, this is the correct range for hydro.

I’ve never had a problem using the pH test drops with any nutrient system and getting an accurate reading. And the pH drops are made by GH for their Trio, there shouldn’t be any problems getting an accurate color reading.

What concentration are you running at in your reservoir? What is the EC/TDS/PPM?

Happy growing,



So I’m not currently monitoring my EC/ppm because I’m a newbie and didn’t know it was required. I dont even know what you mean by concentration haha. Any info or links on the basics would be appreciated.

EC/PPM is a measurement of the concentration, 1tsp per gallon is also a way to think about concentration, 2 tsp per gallon would be a much higher concentration and a higher EC/PPM.

You should know this EC/PPM number in your starting water as well as the starting water’s pH. EC is the standard, PPM can vary kind of like Imperial to Metric, you need to know what the PPM conversion value is to know what it converts to in EC to have the most accurate way of speaking about it with others in a forum, if in the USA, we mostly use the standard 0.5 conversion from EC making everything pretty easy to do in your head, PPM would be about half EC, i.e. a EC of 1.0 would be 500 PPMs.

EC/TDS can be as important as pH especially in hydro.

Are you starting with just your plain water, adding nutrients, giving a few minutes, say 15 minutes for the pH to stabilize before trying to test and adjust the final pH?



Thanks for the explanation. So I am starting with plain tap water, adding nutes, giving it a few minutes then adjusting the pH. I live in a old building in the States if that means anything. What’s the best way to test/control EC?

Digital TDS pens are pretty cheap.

Haha @kabongster, you beat me to it, lol. That is a link to a decent pair of meters.

You do want to find out what the pH and the TDS is in your tap water. If the TDS is too high, or if you have too high of certain minerals (you should also get a water report from your water supply), you might need to invest in a R/O water filter or buy distilled water from the grocery store or somewhere.


just a couple of things that mite help you ,them rooter plugs can give you issues with seeds and seedlings . they hold water almost to well … next you mite give it cal -mag only a little, for seedlings …and get your lighting cycle controlled, so you don’t get a bunch of hermies and last, 600 watts at this stage of growth is a Bit much … can you lower the out put??? Hammer


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Thanks for the tips everyone. I agree 600 Watts is a lot this early but its all I have. I started it out at 50% 42" away but it seemed like the seedlings kept stretching so I gradually lowered it and increased it. I’m not sure on my water temps but I’ll start monitoring that now.

As far as EC I was not aware that was something that needed to be monitored. Any advice on how to control the electrical current of nutes and the reservoir would be appreciated.

I think I figured out the main issue though. I am using one of those liquid ph indicators that changes color depending on the pH to test my water. Well my general hydroponics nutes have colors of their own (pink, brown, and green) that seem to be altering the color of the pH indicator. So I replaced the reservoir with plain pH water for now until my digital pH monitor arrives. The plants seem to be slightly better off now.

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am i understanding , that you can dial down the out put of the lite ??? if you can do so …but keep them close to the lights … seedlings will stretch a bit any way.


I replied to this thread in a different thread! OMG! (Actually it was the same answer it was all about pH)

the color of the newts isn’t changing your pH…

Hammer this guy’s got something going on that I just don’t understand?

Regarding the light, @lj , this is a 600 on 250 setting, 18-20 inches above seedlings, that’s plenty of light and it stays 70 degrees all day at plant tops