DWC flushing times

snocat

Active Member
I used to listen to the people that say 2 weeks minimum some say more,but after thinking about it all your doing is starving your plants and I know I dont like being hungry,my last grow I flushed with ph corrected water for 3 days and I see no diference in the smoke that was flushed for 2 weeks,when Im in my last 2 weeks of flower I dont add back any nutes and let my ppm start to slowly drop,then 3 or 4 days before harvest I change out the res with ph corected water,I usually harvest a plant or 2 a day because thats all I can trim in a night,also I tryed a product called royal flush from humbolt and it was a disaster it foamed up my res so bad it was coming out like lava so dont use that stuff in dwc
 

machead

Well-Known Member
thanks for the replies, i to was hoping for it to be quicker than 2 weeks as all the info i can find says 2 weeks but that was for soil an with it being DWC i think 3 days will be enough.

cheers
 

HSA

Well-Known Member
Mac Head: if you're talking about the 'final flush' before harvest then I'd agree with Snocat and Wiimb, but there are other ways to do it. I use Technaflora's, "Recipe for Success," and they have a pre-harvest formula that they claim doesn't require a final flush but I'm old fashion enough that I still do it with pH balanced water for the last week.

But you may also have brought up another topic that they stress in school; flushing every couple of weeks with pH balanced water to just wash out all the accumulated salts from our nutrient mix. Using Tehnaflora's nutes I haven't done that and Technaflora doesn't require it in any of their literature that I've seen. My instructors say it shouldn't be necessary with my DWC bubble tubs because I change my nutes every other week. Not knowing which flush you were referring to I figured I'd better bring this up because everyone else in our class is flushing after every couple of weeks but I agree with Snocat there it's no fun to go hungry and I don't unnecessarily stress my plants. I hope that helps. HSA
 

kushnotbush

Well-Known Member
3 days tops FTW! IMO I don't think my product comes out any better with a longer flush and sometimes I don't even think it needs the flush. When I flush I change the water every day, the first day I run about 150 ppm nutes to help leech any nutes in my medium, after that PH'd water only. For me I have found that I get the best taste when I have dried them slowly and cured them slow as well. Good luck and happy growing.
KnB
 

HobbyGrower72

Well-Known Member
greetings, mac. I started using advanced nutrients final phase because it didn't make sense for me to starve my plants for two weeks at the end of their lifecycle. I'm pretty sure you can use just about any other flushing agent on the market, AN is just the one I use.

Here's what I do... For an eight week strain (for example) I let them go just about the full eight weeks on their normal nutrient program. when I'm happy with the resin glands, maturity, and ready to harvest the plant I'll use a six-hour final phase flush (according to directions) then straight pH'd water for three or four days (you could go longer if you felt it was necessary). but at this point you're done so you're not waiting for it to mature or resin glands to change; just the flush to be complete. How long that goes is up to you.

I notice the flush starting from the bottom of the plant; large fan leaves will begin to turn pale yellow. A breeder told me to remove some of the fan leaves just after the flush which forces stored nutrients from other parts of the plant to be flushed instead of the fan leaves (cuz they're missing). I've never tried it, personally... he's a pro, i am not.

The whole thing made more sense than any other method I've read, viewed, seen, gleaned, etc... Hope that helps and good luck on your grows.

hg
 

machead

Well-Known Member
yes i am talking about the final flush, I use Canna products an they have a final flush product to so ill just use that for a couple of days then PH'ed water for a day or to.

See how i go.

ill let ya know what it taste like :)
 

VoidObject

DWC/Bubbleponics Mod
Wow I swore I saw a thread like this yesterday..

I flush for two weeks, but I like to be thorough.
 

Niko Bellick

Well-Known Member
I flushed only three days this grow and saw no difference than when I flush for two weeks. Just change water daily til the ppms come under 150 (Which took three days so I went and chopped.
 

snocat

Active Member
I think what you put into your res has an effect on taste,when I first started in dwc I kept things simple I used GH 3 part nutes and it tasted ok,on my last grow I used florablend and koolbloom and the smoke taste alot differant,my currant grow I added floranecter and Im not to sure if I will be adding it in on my next res change,it has started to foam up a bit just like if I were to add molasas to my res(been there done that)its not foaming as bad as the regular molasas did but its still there and I dont care for the smell of it either Im used to my res smelling fresh and clean and now it has an odor to it so Im going to use it for my last week with just that in the res and then a 2 day ph water flush and see if the taste is any differant
 

hydrohomer

Member
I've not flushed at all over the past 3 or 4 harvests and have notice no appreciable difference in the smoke. The black/grey ash test seems to be B.S. too, the only time I've ever noticed black ash is jumping the gun and smoking something that wasn't quite dry yet. Try for yourself and see... Commercial vegetable growers, even locally (I've asked) do not flush their hydroponic tomatoes and lettuce, and we eat them without bemoaning a "nute" taste. I really think the whole flushing this is over-blown and largely mythology that has been perpetuated by a few believers with little quantitative or qualitative data to support anything other than a psychosomatic "because-it-had-nutes-in-it-my-smoke-tastes-like-nutes".

Flusher flame-suit on.
 

Bargar

Well-Known Member
Assuming flushing is a good idea, if I use Reverse osmosis waster exclusively (my tap is freaking .65EC) What ppm/EC should I make my water? I am assuming that I need to add only cal-mag to the water, is this right? I would just use tap water, but at such a high ec/ppm I am afraid of what may be in it!!!
 

HobbyGrower72

Well-Known Member
Flush in hydro is mandatory (my opinion), you can get away with not doing it using organics in soil, but synthetic ferts and salts build up and need to be removed. Can't speak for organic-hydro. Done properly, it greatly enhances the flavor, taste, smell, and burn.

If you're using ro throughout the grow cycle, i would suggest using ro for the flush. Because we're not adding nutrients during the flush i don't think pH is a factor. I could be completely wrong but that makes sense to me. However, adjusting pH certainly wouldn't hurt.
 

Bargar

Well-Known Member
I would really like to know for sure how to flush them using RO.... I dont want to use pure RO if its a bad idea
 

Bargar

Well-Known Member
BUMP! I really want to know what RO users say on flushing times, and if they use cal-mag or not to help with cell division.
 

VoidObject

DWC/Bubbleponics Mod
BUMP! I really want to know what RO users say on flushing times, and if they use cal-mag or not to help with cell division.
I never really thought about RO peeps until now.. but I bet you have shorter flush times than us tap water users eh?
 

RL420

Well-Known Member
"Flushing" is a method to let the plants use up their stored nutrients by not feeding correct? I heard its 2 weeks, maybe less or more based on strain. Also Clearex and all those flush additives are a joke, send me your cash instead im poor as shit :(
 

greenfox420

New Member
you see no need to flush because your not looking at it from a molecular or healthy stand point.... Flushing removes the salts and other trace minerals from the plant which can leave a harshness in the throat or extra Mucus everyday.. The body doesn't reject cannabis as much as all the other shit still soaked into the buds... Flushing is VERY necessary and every top grower in the world flushes.... you can't find anyone BIG in the industry that doesn't. why would you follow local hobbyist when the professional info is EVERYWHERE. Flush your play and just use Magnesium through the last 2 weeks slowly using less and less MAG. this helps to keep your aroma pungent until harvest as I've noticed straight 2 week flushes can cause aroma loss.
 

LivingCanvas

Well-Known Member
Here's a thought:

Now, I'm sure many people will disagree with me, even though I've smoked my own product WITHOUT FLUSH in DWC.
Flushing, is designed to remove EXCESS chemical nutrients from the medium and cause the plant to use up internal stores.

STOP. Let's think for a second. Coco/Soil(with Chem Nutes)/Rockwool are ACCUMULATING MEDIUMS. What does this mean?
It means, when you fertilize those mediums, NOT ALL NUTRIENTS ARE USED BEFORE THE NEXT FEEDING. This creates a
BUILD UP of nutrients that are NOT BEING USED. This is why when someone fucks up their feeding they FLUSH the medium
adjust the feed schedule. A plant that is being fed LESS THAN 1500PPM should not have excess nutrients/chemicals in the root
zone.

In DWC the medium (as in water, assuming no top drip) DOES NOT accumulate. The only nutes available are WHAT IS IN THE WATER.
If you do not OVERFEED (above 1500ppm - YES, you can go higher than 1500ppm *however* NO STRAIN NEEDS IT to thrive) there
is no need to flush. Why would starving your plant help it?? Starving an animal/person only opens it up to disease/pathogens.

-Base point: As long as you lower your ppm/do not overfeed - in *DWC* you should not NEED to flush!!! You can do it if you want,
but if will reduce yields. 3 days shouldn't hurt.

One other point - What pH does cannabis flush best with? If it is *WATER ONLY* you don't need to pH it!!!!!!!!!!! Why? Because we
adjust pH to increase NUTRIENT UPTAKE EFFICIENCY!!! NOT WATER!!! I have seen NOWHERE on ANY CHART, where a plant will drink
water only if it's at a specific pH -OR- that a plant can only take up water if it's pHed!!!

Let's stop pushing rumors, and people's opinions over SCIENCE.

P.S. Clearex and many/most other "flushing agents" are SUGAR WATER. Go read the label - glucose and sucrose. Aka. Sugar.

As far as greenfox is say, that all "professionals" flush... that doesn't make them correct or conscious of the actual molecular reasons. SALT aka CHEMICAL based nutrients are salts because of SOLUBILITY. Aka, it can dissolve in water. Once they are taken up by plants, they are CONVERTED, from salts, into different compound required for plant metabolism. The main thing with CHEMICAL NUTRIENTS, are that they are in plant usable form, and are *forced* into the plant through a difference in osmotic pressure.

I know a number of professionals, have discussed science with them, and a lot of people can't agree. This is mainly because they DON'T KNOW SCIENCE. I'm taking people who run 200,000 watt warehouse dispensary grows. The same people who ask me when they can use Eagle 20 for PM (remains in plant 50 days, is carcinogenic) and people who light off bombs in FLOWER. And these are professionals... as in they get PAID to grow weed. Granted, most of them got paid the same or less to grow weed, as I got paid to recommend the appropriate remedies and nutrients for clients.

I see A LOT of "professionals" who don't know very much, and a lot of professionals with big heads because they grow weed. Well... if you knew what you're doing, why grow weed for someone else? And why do they come to me, asking advise, when they're "professional/commercial" and I'm just some small timer who actually cares about learning, trying new methods, and studying rather than telling everyone who will listen about my "donkey dick colas..."
 
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