Hey folks. I'm taking my first crack at ebb and flow using rockwool and hydroton. I made the mistake of not feeding often enough and now have deficiencies. My question is how often can I feed to correct this problem? I was feeding twice a day when the problems arose(in veg, lights on 24 hours), so should I up it to 4 times a day? More than 4? My nute strength is around 700-800 ppm, PH at 5.8-6.0 and water temp around 70 degrees. Thanks folks.
Ebb and Flow Feeding question(to correct deficiencies)
- Thread starter skinzilla
- Start date
Assuming your nutrient solution has all a plant needs and you ph is where you say it is, you shouldn't have deficiencies.
Not feeding often enough? Was it drying out between floodings? If your media is mostly hydroton, you will need to flood much more often than if you were only using rockwool. But even then, you shouldn't get deficiencies, you plants will just droop.
You have any pics?
Not feeding often enough? Was it drying out between floodings? If your media is mostly hydroton, you will need to flood much more often than if you were only using rockwool. But even then, you shouldn't get deficiencies, you plants will just droop.
You have any pics?
Here's some pics. Yes, my media is mainly hydroton(the plants are in 4 inch rockwool, everything else is hydroton), so I think it's safe to say they dried out between floodings. Is it possible my PH could have caused these problems? It's never been over 6.3 and I'm fairly anal about keeping my trimeter calibrated, so i didn't think PH would be the problem. Here's some pics, but they're not the greatest(lights are on). Thanks Sam.
youngtrader9689
Member
what nutes and what npk values? u look like u could use a lil mg or iron
Stond_Face
Member
Hmmm. they don't look happy at all.
I run E&F, but with coco.
I would not bother to figure out what the deficiency is exactly; I would prepare a fresh rez., and rinse out the medium of the plants.
I shoot for an EC of 1.5 at first. Then raise it as the plants request.
I think the medium drying out is the cause of the trouble. As the water drys from/ or is used from the medium, its EC goes up. This probably caused a lockout. That is why I say a good media rinse is called for.
Cheers,
S_F
I run E&F, but with coco.
I would not bother to figure out what the deficiency is exactly; I would prepare a fresh rez., and rinse out the medium of the plants.
I shoot for an EC of 1.5 at first. Then raise it as the plants request.
I think the medium drying out is the cause of the trouble. As the water drys from/ or is used from the medium, its EC goes up. This probably caused a lockout. That is why I say a good media rinse is called for.
Cheers,
S_F
MPL
Member
If you don't flood often enough and the medium gets too dry, it can cause pH issues.
Example: plant is using more water than nutes (fairly normal, especially during veg as in your case). If you start evaporating all of that water, because the nutes aren't being taken up quickly enough to compensate for the extra evaporation, you are going to increase the EC and usually lower the pH. A combination of high concentration nutes, plus possibly altered pH, plus essentially starving to death = lots of uptake problems. On top of that you've got the nutrient salts deposited all over the roots and grow medium. The dry salts will suck more moisture out of the plant on top of the damage they'll do on their own. Plants drying out in hydro systems is bad bad mojo.
I'd do as Stond Face said and dump your res and start fresh. I usually got for a somewhat lower EC in situations like this (1.2), but 1.5 should be fine. Make sure you take good care of them and in about a week (or less) they should be back to rapid vegging!
I'd adjust your flood schedule to once every two hours, for five minutes per flood (if you can fill your table in that time) and adjust from there. Slowly increase the length between floods while carefully watching your plants. You want them to be right on the edge of drooping when the next flood comes.
Example: plant is using more water than nutes (fairly normal, especially during veg as in your case). If you start evaporating all of that water, because the nutes aren't being taken up quickly enough to compensate for the extra evaporation, you are going to increase the EC and usually lower the pH. A combination of high concentration nutes, plus possibly altered pH, plus essentially starving to death = lots of uptake problems. On top of that you've got the nutrient salts deposited all over the roots and grow medium. The dry salts will suck more moisture out of the plant on top of the damage they'll do on their own. Plants drying out in hydro systems is bad bad mojo.
I'd do as Stond Face said and dump your res and start fresh. I usually got for a somewhat lower EC in situations like this (1.2), but 1.5 should be fine. Make sure you take good care of them and in about a week (or less) they should be back to rapid vegging!
I'd adjust your flood schedule to once every two hours, for five minutes per flood (if you can fill your table in that time) and adjust from there. Slowly increase the length between floods while carefully watching your plants. You want them to be right on the edge of drooping when the next flood comes.
Last edited:
Did someone mention SOG?
36 CLONES, 3X3 TABLE, 1000W, STRAIGHT HYDROTON
GROWING AND FEEDING
Clones straight on to 12/12.
Res changed every 2 weeks.
pH 5.8, EC 1.2 at start, increased .1 each week to a max of EC 2.0
Flood 15 minutes every 3 hours during lights on, 15 minutes once during lights off.
Works for me.
36 CLONES, 3X3 TABLE, 1000W, STRAIGHT HYDROTON
GROWING AND FEEDING
Clones straight on to 12/12.
Res changed every 2 weeks.
pH 5.8, EC 1.2 at start, increased .1 each week to a max of EC 2.0
Flood 15 minutes every 3 hours during lights on, 15 minutes once during lights off.
Works for me.
MPL
Member
For sure dude, keep us updated.
I don't know if you realize this but you're actually kinda lucky you still have a crop. You just about killed every one of your plants. Letting plants dry out in hydro is one of the absolute worst things you can do. If you had added just one more hour to the flood interval they may very well have straight up died on you.
Cheers!
I don't know if you realize this but you're actually kinda lucky you still have a crop. You just about killed every one of your plants. Letting plants dry out in hydro is one of the absolute worst things you can do. If you had added just one more hour to the flood interval they may very well have straight up died on you.
Cheers!
MPL
Member
Sorry to hijack, just a couple of quick questions:
What strain? How much pruning? I've never tried SOG and am about to embark on my first effort with it. I'll be using slightly fewer plants per sq. feet but that's essentially the type of growth I am looking for.
What strain? How much pruning? I've never tried SOG and am about to embark on my first effort with it. I'll be using slightly fewer plants per sq. feet but that's essentially the type of growth I am looking for.
Did someone mention SOG?
36 CLONES, 3X3 TABLE, 1000W, STRAIGHT HYDROTON
GROWING AND FEEDING
Clones straight on to 12/12.
Res changed every 2 weeks.
pH 5.8, EC 1.2 at start, increased .1 each week to a max of EC 2.0
Flood 15 minutes every 3 hours during lights on, 15 minutes once during lights off.
Works for me.
This is a 100% indica strain I have maintained for about 12 years. It is a clone strain only although recently I produced feminized seed as a backup.
Therefore I have constantly been keeping mother plants.
I grow single cola style, 4 per sq/ft and trim off any lateral growth from the main cola. I have used these offcuts as clones up to 3 weeks into 12/12.
One must have healthy mums and a very reliable cloning method to do SOG's and not be to concerned about plant numbers.
Cheers.
MPL
Member
Recovery is well on it's way. I think I had my PPM a bit too high while correcting the problem, so I've stepped it down to 750ish now and will see how things respond over the next few days. If anyone's still paying attention to this thread, I've been feeding every 2 hours to correct the nute deficiency. Should I step back on my feeding frequency too, or just cut back to the 750PPM and see how things go?
MPL
Member
What are your temps at? Its hard to tell but it looks like they might be a bit on the warm side.
The best way to see if your plant is recovered is to see if it has started growing again, and how quickly. Also don't judge too much based on seeing the leaves themselves recover. Usually a leaf, once damaged, stays damaged. Instead, look at the new growth. Do those leaves and stems look healthy?
Generally I'd say your plants are looking decent. Check your temps and let us know where they are it. At the top of the canopy they need to be around 75F.
The best way to see if your plant is recovered is to see if it has started growing again, and how quickly. Also don't judge too much based on seeing the leaves themselves recover. Usually a leaf, once damaged, stays damaged. Instead, look at the new growth. Do those leaves and stems look healthy?
Generally I'd say your plants are looking decent. Check your temps and let us know where they are it. At the top of the canopy they need to be around 75F.
Thanks MPL, my temps are around 78-82 at top of the canopy, so I'll dial down the a/c a bit. My new growth looks good, but some of the leaves are dark green with deep ridges, which i'm pretty sure is from having my nutes a bit strong, but maybe i'm getting that confused with the temperature issue? Hopefully over the next week things will look a bit better with lower ppm for my nutes and the temp issue fixed.
MPL
Member
Get your temps to 72F-76F and I think you'll see that everything kind of fixes itself.
Don't change anything else until you get your temps in order!
Don't change anything else until you get your temps in order!
