newbie pH troubles

Hi all! I've been growing for a few years but I've a complete noob when it comes to hydroponics. I just started using some very basic DWC buckets, and I seem to be having some trouble with the pH.

The pH has been fairly stable until recently, when it suddenly went from 5.8 to 5.5 in three of my buckets, resulting in yellow, spotted leaves. One bucket in particular really wants to drop its pH, and I've had to add 20 drops of pH up for the past two days to keep it around 5.9 (this bucket's nutrient PPM went too high recently, resulting in nute burn, coincidence?).

As I understand it, there are two reasons for dropping pH. The first is an increase in the PPM of the nutrient solution, which hasn't been the case here. The second is root rot, which does not appear to be the case either since my roots are very healthy and white (a little pink from the Lucas Formula, actually).

The reservoirs have been given nothing but RO water, and 0-4-8 strength Lucas Formula, except for the one that got 0-5-10 (burned my plant). PPMs range from 350 to 450 currently.

I am using a GH dual-diaphragm air pump in 4 buckets with large ecoplus airstones, which I believe should be sufficient to avoid root rot.

Any thoughts or ideas would be helpful. I'm thinking of adding 3% hydrogen peroxide in case there is microbial life in my buckets... and perhaps more air...

EDIT: I forgot to add that there is a *slight* fish tank smell in my buckets. I usually associate that with microbial activity...

Dump your nute solution and run a h202 cycle for a day. I would ditch the lucas formula......I had problems with the lucas and since switched to AN. I actually called them and gave them my whole layout and they did all the math and told me what amount I should be adding to my bucket. Smooth sailing since then. Also whats your rez temp at?

Lowering of Ph could be lockout too..... thats what AN told me.

I actually haven't taken rez temp readings... The space is at 78 degrees all day long under a 600w HPS. Seems to be standard for DWC buckets.

How much peroxide should I use per gallon? I have the 3% stuff with no additives other than water. And is it ok to put my plants in with the peroxide?

I'll dump my reservoirs and refill... they are almost 2 weeks old. I was just going by the "dump your reservoir once you've topped up with an equal amount of water" rule. So much for that.

Peroxide I have no idea. I would just say a couple cap fulls...or google it lol. For real though I would drop that lucas shit..... its garbage.

And 78 is too high man......needs to stay below 72 or root will take hold. Just add a few frozen water bottles to your bucket.

root rot* soory for the error

I should be moving my space into the basement in a month or so... this will keep temps down. I think the reservoir is somewhere under 78 since that's the ambient air temp up near the lights.

The Lucas Formula doesn't work? Rumpleforeskin seems to get fantastic results with it... and when I'm not killing my plants with pH issues they grow quickly and look healthy!

Right now I'm waiting for my RO filter to pump out half a bucket's worth of water. Meanwhile I'm rigging up more air pumps so that my GH pump only has to take care of 3 buckets. Also, googling peroxide dosages...

Thats the problem I ran into with the lucas...... too many problems for what should be a simple feeding regime. But what could be more simple than mixing up a bucket of nute solution and only checking the Ph every other day and adjusting it as needed. When I called AN I was shocked when they told me to mix at 1/5 strength TOPS. The bottles I have will last forever. Lucas also turned my roots an orange color.....I didnt like this. AN gives me straight up WHITE roots and its pretty much check the Ph and thats it. I mix a new bucket up every week and the plants love it. But if the lucas works for you than use it but its sounds like youre running into the same problems I did thats why I changed to AN.

I'd say you might have three problems.

1: being you have non beneficial bacteria growing in your buckets(that's what the smell most likely is). To fix this I have tried Hydrogen Peroxide and had ok results(if using %3 you can dump the whole bottle into your system and be fine, the stuff I was using was %27 Hydro Grade) I've grown DWC for five years now and feel I can authoritatively say Dutch Master Zone is the absolute best product to keep your DWC root zone stable and clean. However, I did go from H202 to Zone in the same grow (My system is all connected and recirculates) and practically killed my plants. So if you go to Zone (my recommendation) I'd do a complete changeout of your water and then use the Zone bottles "aggressive formula". The problem with using products like Zone is that they kill ALL bacteria and fungus, so you don't get any of the beneficial ones. Personally, it's a trade off I'm happy to make.

2: You might have a CalMag deficiency because you're using RO water the Calcium, Magnesium, Boron, Zinc and most other micro-nutrients are being filtered out. Get some Cal-Mag and it will go a long ways.

3. Per your post, you are giving them zero Nitrogen (0-4-8 and (0-5-10). It's one of the three most important nutrients to your girls. I have never used the Lucas Formula, but have a hard time believing folks are successful through a grow with zero N.

If I were you, I'd drain my buckets and mix up the GH standard 3 part at about 1/3 strength, add zone, diamond nectar (humic acid), and Cal-Mag. I'd bet you'll see a significant difference. Today, I use nutes from a company called Cutting Edge. It's nearly the same as the GH 3 part, but a few bucks cheaper and seems cleaner (less salt build up) along with the nutes mentioned above and in budding I use liquid koolbloom for the first two-three weeks. Then go to the powdered koolbloom, which is a very different N-P-K ratio from it's liquid sister. Not sure why they chose to brand them the same.....but what do I know. I'm just a DWC lover who enjoys to puff! Seriously hope this helps bud!

haha no, 0-4-8 isn't N-P-K. It's Lucas Formula code for 4ml Micro and 8ml Bloom per gallon (GH Flora nutes). I see how that could be confusing though.

Thanks so much for your help guys! I was really hoping to scratch by without having to invest in 50 bottles of additives. It looks like I will be picking up some Zone at the very least. This first hydro grow has slapped me with every rookie mistake, but it's good experience.

I suppose that I was just getting lazy and pushing my reservoir changes to the limit. I did have some really healthy growth going until the pH started crashing, so I'm thinking that the additional air I rigged up, more frequent reservoir changes, and a cleaning additive will do the trick. If not, I'll have to look into more drastic measures...

Thanks again for all of the help! You guys are speedy!

more air is always better. But I'd highly suggest getting this pump:

http://www.amazon.com/Sunleaves-SDA530-DuraPump-Air/dp/B0013UZTIO/ref=sr_1_1?ie=UTF8&s=home-garden&qid=1301034590&sr=8-1

600 GPH!!!!! vs the General Hydroponics one which is almost 20 bucks more and produces roughly half the air!

Glad you clarified the lucas thing. I've read up on it before but it was a long long time ago. I just use the mfg. recommendations but try to cut them in 1/3 or 1/4th as DWC doesn't need as much as other Hydro systems. For small plants stay under 400 ppm, mid range 400-700, monsters can go as high as 11-1300 and still not burn. From my experience. As a side note, I primarily grow indicas. So these ppm readings might not apply the same to sativas. I'm just not experienced enough to speak to it. Sativas make my heart race and get paranoid. Indicas make me mellow and want to eat everything in my fridge

Bahahaha I'm currently stuffing granola cereal into my mouth while puffing on Afghooey, so I'm with you there.

I looked at those commercial pumps when I made my purchase... everyone said they were ridiculously loud, which would suck here in my office. That's why I went with the GH. It's quiet and it seems to be bubbling up a storm with just 3 buckets. 4 buckets was a bit of a stretch, I admit that now.

One more month until I get to expand my grow space into the basement... part of that will include one of those crazy air pumps... >

beefxer said:

Bahahaha I'm currently stuffing granola cereal into my mouth while puffing on Afghooey, so I'm with you there.
I looked at those commercial pumps when I made my purchase... everyone said they were ridiculously loud, which would suck here in my office. That's why I went with the GH. It's quiet and it seems to be bubbling up a storm with just 3 buckets. 4 buckets was a bit of a stretch, I admit that now.
One more month until I get to expand my grow space into the basement... part of that will include one of those crazy air pumps... >

Click to expand...

Ha! Your reply makes me smile I can attest the sunleaves pumps are loud. I use one pump for six buckets (One reservoir and five grow buckets) and get more than enough airflow. I have the GH model you have and keep it on a shelf as a backup. Should anything ever go wrong I could take the four outlets off the GH and McGyver something together to get through a day or two until I could get another Sunleaves. For what it's worth, I have six or so grows on that pump with zero issues. The only way it could be better is if it was more quiet as you pointed out. But it's a small price to pay for the reward of the 600GPH! Enjoy your cereal!!!

I've read hydrogen peroxide 3% you need to use about 3ml/l, that's what I do, with good results I think

Everything seems to be under control now. I passed a bucket of plain RO water pH'd to 6.3 around, letting each plant soak for several hours. I'm also in the process of changing out all of the reservoirs... one left to go.

I added peroxide at about 10ml/gallon. I hope that works...

It does seem that my reservoir temps must be too high. Ambient temp in the room outside my grow tent hovers at about 73 or 74, so I imagine that my reservoir is somewhere above that... not so good. So, moving into the basement is a great idea... and I'm also thinking of switching to 12/12 and letting my lights come on at midnight and off at noon, which would cut down on heat quite a bit I think.

Thanks everyone for your help! I'll post pics when my garden isn't an embarrassing, yellow spotted mess.

The PH level of the soil for better growth is 7.0PH as per calculation,
distilled water consists of the PH value 7 so try watering with distilled water for sometime,
lets check the solution for this..

Erm, this is for a DWC bucket... as I understand it 5.5-6.8 is quoted as being the range for cannabis, but I'm aiming for 6.0 right now.

I'm open to suggestions, because I'm a hydro noob.

I figured out what my problem was. The comments I got here about reservoir temperature got me thinking, and I realized that I had started to keep my tent open during the lights on cycle. It seems obvious now, but it was screwing up the air flow in my tent: hot air out the top, cold air in the bottom.

Long story short, my reservoirs got too hot, my roots started to die, so my pH started to drop and my plants started to look like they had nutrient lockout.

So all you noobs out there should take heed: if your roots aren't gleaming white and growing aggressively, you have a problem. If your pH is dropping, you have a problem. Make your reservoirs light tight, and make sure they stay under 72 degrees!

Thanks again for everyone's help!