Any body care to venture a guess as to what's happening? I just switched from three Aerogardens to two six hole bubble tub DWC's and so far so good. Granted this is my first experience with this style of growing and so far I love it but some thing strange is going on in my reservoir. I've never had healthier, happier plants but their nutes are suddenly turning acid. I'm using, exclusively, Technaflora's "Recipe for Success," (Which I've used for for over two years and been very happy with). Instead of my pH climbing as it always has in the past it's dropping radically. In the past I would set it at 5.8 and the next day it would be in the low to mid 6's. Now I set it at 5.8 and it's between the low 5's and the high 4's. I figured it might stop when I changed the nutes yeaterday but it didn't. The hydro store is stumped and I'll try to get an opinion from Technaflora and my hydro teacher when I see her, but have any of you had this experience? I can't really call it a problem since my plants a happy.
Trichrome Fiend: it's filtered, irradiated RO'd water from the supermarket kiosk, the best we have available. what do you think? Hank
...I've never had any problems with RO'd water. I also use RO water....I just add my fertilizers and everything falls into place. Maybe it's your fertz ...I've never used that name brand, sorry no help.
Trichrome Fiend: yeah it confuses the hell out of me too. The water is from the same source I've used for the past year and I'm using the same brand of nutes I've been using for the last three years. Maybe it's a growth stage I've never seen before? I just finished checking their pH's and the one I changed yesterday did go up to about seven. That's higher than it always had but the one I hope to change tomorrow still went down to about 4.9 Have you ever had healthy vegging plants do that? I haven't. Hank
...nope, never. I use the Lucas Formula throughout my whole grow....I even use a quarter strength Lucas in my aerocloner (when that time comes) and I never have a problem. Ever ran the Lucas?
I hate to tell you this but it sounds like you have a root bug. You can't totally kill it but you can stave it off. Not the end of the world though you have several options; Double your air, buy another air pump or two. If you are using any sugar product stop. Hydrogen peroxide will kill the microbes somewhat, but if you use too much you could damage your plants. 1 teaspoon per gallon. Enzymes can work, (hygrozyme, sensizyme or cannazyme) and you will need to use them for the rest of your grow. Go biological, brew a microbe tea and add it to your reservoir to crowd out the bad bacteria, again you will need to add it for the rest of your grow. Look in the organic section. Buy a chiller. There are many root diseases and what works for one doesn't work or another. Best of luck
Mile: I ran my problem and your suggestion by one of the more knowledgeable guys at the hydro store and he suggested something I'd never thought of. He asked me what kind of lighting I was using and when I told him T-5's he asked me how close I had them to my plants. When I told him one to two inches a little light went on in his eyes. He suggested it might be the close proximity of the lights causing the downward swing in pH. Evidently he's seen this before. I know the manufacturer recommends six inches to a foot clearance. What do you think?
Maybe, in a healthy reservoir if your nutrient solution is too strong your plants will use more water than nutes and your Ph will go down as the nutrient concentration gets stronger. If your lights are close and causing your plants to use too much water the same situation could happen. I would be a bit skeptical that a T5 could cause this. Even so if that was happening you would see a minor Ph drop like .2 to .5. If your top 2 sets of leaves are “canoeing†your light may be too close and or humidity too low. The only time I have seen a drastic drop in Ph is from a root disease, I talking a full point or more in a day. The cheapest and easiest thing to try would be put ½ teaspoon per gallon of 3 % h2o2 in your rez and see if the Ph stabilizes, if it does then you know you have a root problem.
the rate of ph fluctuation is a function of not only what's going on in your res but also how large your res is. if you have a small res, you're going to see larger ph swings more frequently. ph dropping like that usually happens during the middle of flowering. if you have a "root bug," it should be readily identifiable by looking at your roots. unhealthy roots are pretty noticeable. if your roots are looking fine, try switching up your nutrient formula. use less nitrogen and more potassium. you can also use silica products like silica blast, grotek protek, etc. to adjust your ph if you don't want to top it off. it will re-add the potassium that's missing and raise your ph to a more acceptable level. regarding the lights being very close, the more intense the light is, the more nitrogen you're going to want relative to potassium. this is a pretty basic fact of soil science. unless you're getting light burn, i'd say your lights being close has nothing to do with your ph swings.
makes a good point, you should also check your ppm/ec and see how it moves in relation to your ph. it would also be helpful to know what you're nutrient profile is.
Dunny: Thanks. The worst of it seems to be over. I've got six plants in each tub vegging and now they go up from 5.8 to about 6.1 every morning which was normal before all this started. I added a half ounce of H2O2 per gallon just in case there was something going on in the root zone but the roots are healthy and the tubs are clean. Since both tubs did the same thing, the plants are all the same age, and now it seems to have self corrected I have to assume it was related to the strain and their growth stage. The plants have been healthy all along so I wasn't scared, just curious. Our hydro instructor didn't have an answer either. She said to just leave them alone if they're happy. When they're happy I'm happy. If it happens again with another grow I'll know not to panic. I've documented it for future reference. Thanks again, Hank
I had this problem about 8 years ago and found out that my reservoir was getting to hot and it was evaporating to much water when my plants was small. The dehumidifier also needed adjusting.
Greenwater: it is a brain teaser, isn't it? The problem, if it ever was one, seems to have self corrected. My plants got a half dose of flowering nutes yesterday and went under the flowering lights. The last couple of weeks they returned to their old habit of of going up from 5.8 to about 6.1 to 6.2 in 24 hours. This was normal in the past on all my other grows with my Aerogardens but this time when they were heavy into vegging last month they were going acidic; from 5.8 to sometimes as low as 4.5. This has puzzled the more knowledgeable guys at the hydro store and two of our hydro instructors at school. One, who has a tendency to get real technical on us, said to isolate all the variables; a new 2' by 4' tent, new DWC bubble tubs and a rack of T-5 grow lights. Another one, when I told him I was using T-5's real close to the tops of my plants like I had with the Aerogardens suggested it might be that. A third instructor asked how they looked? When I told him they looked better than they ever had before he said, "Not to worry. take 'em back to 5.8 and let them do their thing." And that's what I did. Eleven out of twelve made it so far with what I consider to be spectacular results. I figured you guys on the forum collectively might have run into this. I don't think the temperature was too likely a cause. I grow with the tent open during the day and 'round the clock temperatures of 73 to 75 degrees pretty much year around. When we go to sleep I drop the thermostat to 73 and turn on the Can Fan and zip it closed with the lights off and the rear vents open. There's a constant air exchange with the Can Fan in that little tent and the recorded high is never more than 75 max. As long as there's no stress on my plants I'm going to continue to let nature take it's course but if it happens again at least I'll know not to panic. I guess that's why they sell us both pH UP and DOWN? Thanks for your response. Hank
what's bubblin! I have found in the past that some days are good some are bad. I have been straight hydro for about 10y. I have my own special breed that I have developed over time. The first hydro, 10 years ago I started was aero and G13 of course I had to do my aero with holes in a garden hose because we could not find the spray nozzles like now. I had some bad results and problems like the one's in your area. I grew and grew good but to many variables to contend with. Now i use a hybrid system part dwc and part nft. I have consistently no problems ever with clogging or nutrient problems unless I do not filter water and get down to under 50 ppm in my initial water before nutrients. Now I just focus on my breeding and trimming. If you guys have any other problems i've been doing this for a while and maybe we can help each other. Have you ever tried to drop the temp in your room to about 68 and never go over 72. I have saw in breeding that some plants like it lower some higher. I research a lot on different breeds and depending on where the breeds are from is how they like it. Even on water temp can make all the difference in your final product and quantity.
Greenwater: your comments on temperature have not gone unheeded but the cost of setting the thermostat and dropping the temperature into the sixties this time of year where I live would be prohibitive for me. I suspect that a lot of you guys and gals are growing commercially for profit and all I'm trying to do is keep my sugar bowl full as inexpensively as possible. I'm retired and trying to live on a pension so I grow my meds and only for myself. A friend suggested medical marijuana over the codeine the Md's were feeding me on increasingly shorter schedules and for the last few years I haven't needed it. I have a sweet little nameless stinky Indica that after a few puffs off my vaporizer relieves my pain in a fraction of the time prescribed drugs did. and it lasts just about as long. Right now this bubbling DWC is a new adventure for me. Previously I grew my meds in three Aerogardens; the patented complete growing system, (one for each stage of development). That was my apprenticeship to hydroponics. I could only grow one or two plants in my little A/G's and it had to be a continuous 24/7/365 days a year operation to keep my bowl full. A friend bet me a hundred bucks I couldn't grow with anything else so I took him up on it. I did the research for what I thought I needed and decided on a 2 by 4 tent, a Can Fan with a carbon filter, two six hole bubble tubs and a rack of T-5 lights. It's added up to about $800 so far and so far so good. I've essentially knocked off Stealth Hydro's bubble tub from their video with spectacular results unlike anything I've ever had before. When I have my legal quantity and a handle on the time line to produce it I'm looking forward to trying some legal crops that won't make it outside in my climate. I have a nice dirt garden in the back yard but nothing like what you can do hydroponically. So far I'm entering week nine on the progressive light schedule that started at 20/4 the first week. It's at 13 on and 11 off right now. I put the red flowering lights in the T-5 rack this week and they'll go down to 12/12 next Tuesday. I'll keep dropping the light to 14 off and 10 for the rest of the flowering period as I've found that a better schedule on CFL's than 12/12. I'll save the six best plants that start flowering and figure on about six to eight more weeks before flush and harvest. But a lot will depend on what I see through he scope. One thing I plan to do is to still use the two bubble tubs, but I'll give them new lids with only three holes per lid to give them a little more space. What do you think so far? Hank
You are doing great man! Keeping your cost down and growing what you need. Dwc is a great way to go. i guess you have something like back or neck pain or certain types of migraines for the indica to be working. Question, are you working with seeds or a mother plant
Greenwater: Osteoarthrosis destroyed my major joints. So far they've replaced both hips, one knee and I have compressed cervical discs and three herniated lumbar discs. They were feeding me codeine like candy. I'm growing from seeds now will probably go to clones next. Hank
Man I'm sorry to hear that. I've got to work for the next two days but after that I'll be working on my blog about mothers and clones, maybe I'll have some ideas that you might like. I have some stuff already on my blog. Green Water
When you "transplant" in hydro, give them straight water for a week and make sure there's enough air. Two main reasons for pH creep/drop are nute overdose or not enough bubbles. Good luck.