Flushing first DWC grow

Substrate aside, and going back to the topic, I never flush; ever. I never go above 1.2EC, either. Large plants, tastes great. Great yield. Some harvests better than others, but normally around 1g per watt.

3squared said:

No they don't. They get a lovely yellow as the plant cleans out residuals from the leaves. OP has other issue's going on from the way his leaves are cupped down and curling. A toxicity issue that was there before the flush, not because of the flush.

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That's what is so weird,his plants looked great,nice and green, before the flush, then they got rusty and look toxic. Very strange.

3squared said:

I run DWC and flush the last 3 weeks and a minimume of 2 weeks. Straight potash for a week, clear for a week and then water for a week.

After feeding them chemicals for months our plants could never clean themselves out in a few days, and I surely don't want to be smoking it or tasting it in our products. And we run one of the cleanest nute systems on the market but it's still synthetic.

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That's rediculous with dwc. As long as you don't trash the plant with chemical Nutes the whole run, the plant can definitely clean all of itself out and start yellowing in less that 3 days...

The 3 week flush idea originated with soil. As soil takes 2 to 3 week to "flush" out all the nutrient salts built up in the soil. Dwc I can literally swap my water to 0ppm in 5 seconds and there are no built up nutrients...

All you're doing with a 3 week flush in dwc is decreasing yield.


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70's natureboy said:

That's what is so weird,his plants looked great,nice and green, before the flush, then they got rusty and look toxic. Very strange.

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Yeah, this looking at a pic and reading a few sentences isn't exactly the best way to figure some of these things out.
Nutes, dosage, water temps, ph levels, stain, man the list of factors can go on and on.

All great discussion so far. Personally I know all my parameters were in line such as temps, humidity, ph, ec, etc. It wasn't until I added a well recommended flushing agent that things got nasty. There are a million flushing posts on all the forums and the only clear info is that the community is split on need or effectiveness and that the only way to figure it out is personal trial and error. With that said, I'm still curious if anyone ph's to 7 to lock out the plants regardless of weather your doing a 3 or 10 day flush?

My rez climbs up close to 7 by the next top off while using our Flushing agent, but we take it back down to 6.

Some products require different ph levels, so you might what to check the bottle for a suggested level. My line calls for 5.8 to 6.0 yet others suggest low 5's.

Flushing simply only removes salt build up in the root zone in soil grows. The thought process that you're removing chemicals and bad/unwanted flavor from your buds is crazy talk. Where does this unwanted chmical or flavor go? Back down the stalk? Does it get evaporated off? There isnt any science behind flushing. Does feeding water the last few days/weeks remove the nutes you've been feeding the whole life cycle of the plant?? Does that make sense? A few days or weeks to fix something you've been doing for 4+months? If pushing water on your plant is supposed to rid your plant of extra nutes, where does the nutes go? Does it just up and leave your buds? Just trying to figure out the thought process of how the unwanted nutes and flavors leave your plant..maybe looking up how nutes are used and broken down on a micro level will help you determine if you have a reason/need to fush....

Mhogs said:

Flushing simply only removes salt build up in the root zone in soil grows. The thought process that you're removing chemicals and bad/unwanted flavor from your buds is crazy talk. Where does this unwanted chmical or flavor go? Back down the stalk? Does it get evaporated off? There isnt any science behind flushing. Does feeding water the last few days/weeks remove the nutes you've been feeding the whole life cycle of the plant?? Does that make sense? A few days or weeks to fix something you've been doing for 4+months? If pushing water on your plant is supposed to rid your plant of extra nutes, where does the nutes go? Does it just up and leave your buds? Just trying to figure out the thought process of how the unwanted nutes and flavors leave your plant..maybe looking up how nutes are used and broken down on a micro level will help you determine if you have a reason/need to fush....

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If you read back we already decided to not do the whole flushing arguement thing. We all have read our fair share of reasoning from both sides of the arguements and it never gets anywhere. Everyones just gunna do there own thing in the end.

It's like how you don't talk about religion or politics, same with flushing and defoliating lol

Med4us said:

All great discussion so far. Personally I know all my parameters were in line such as temps, humidity, ph, ec, etc. It wasn't until I added a well recommended flushing agent that things got nasty. There are a million flushing posts on all the forums and the only clear info is that the community is split on need or effectiveness and that the only way to figure it out is personal trial and error. With that said, I'm still curious if anyone ph's to 7 to lock out the plants regardless of weather your doing a 3 or 10 day flush?

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This is the first time I saw the part about a flushing agent. That's the problem. The whole notion of shocking plants into lock out is just crazy to me. It's just not natural.bro.

Yes your right. It is a great read article. And a big thing I like right away is how you can call advanced and be like hey I'm growing train wreck with this system and this and this. How should I use your product. And each support person has there own way of doing things so you will get a varied answer. What Andy at advanced told me for my dwc system is in the final week to use final finish in the first 2 or 3 days or 1 day I can't remember exactly then finish of with plain ph d water. For people who say they don't care to flush they see no difference well that's just bullshit. Because nothing worse then getting shitty tasting black burning weed. I would hate to eat food grown with nasty shit but we do anyways in this world but when we have a choice to make a better cleaner healthier product then fuck yea

BusterVAP said:

Yes your right. It is a great read article. And a big thing I like right away is how you can call advanced and be like hey I'm growing train wreck with this system and this and this. How should I use your product. And each support person has there own way of doing things so you will get a varied answer. What Andy at advanced told me for my dwc system is in the final week to use final finish in the first 2 or 3 days or 1 day I can't remember exactly then finish of with plain ph d water. For people who say they don't care to flush they see no difference well that's just bullshit. Because nothing worse then getting shitty tasting black burning weed. I would hate to eat food grown with nasty shit but we do anyways in this world but when we have a choice to make a better cleaner healthier product then fuck yea

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then why are you using chemical salts to grow your weed? if you were so concerned about your health, you'd use organic ferts.

From what I know the advanced nutrient line up consists of synthetic and organic materials depending what line up you have. And whether your using organic or synthetics a flush should be done. But I've yet to experiment fully so don'the take my word for it but it does make sense to me

Also advanced nutrients is the only company that grows and supplies medical cannabis to the shops and stores in British Columbia. They have put millions of dollars into research and even more into fundraisers and everything else they are involved in. 8 out of 10 cannabis cup winners use advanced nutrients. If there research and product is good enough for the medical industry then awesome.

First time growing in DWC or hydro for that matter and I'm wondering if I can continue to use my Hydroguard and only that no Nutes during flushing. My water temps run a little warmer than I'd like and id hate to get root rot or any other issues my last week or 2. I know people suffer in opinion hen flushing is brought up and to be honest I'm on the fence myself but just curios if using the H guard would would cancel out my attempt to flush. Many thanks for your replies

From my understanding, "Flushing" or "to Flush", as defined by google is:
cleanse by causing large quantities of water to pass through it.
"flush the toilet"

DWC can't be flushed, as you just dump the water and refill. When the term is used in growing Cannabis, it's for cleansing Soil.

People are confused as to "Flush" by cleansing soil, and to "withhold nutrients" at the end of Flower, to break the Chlorophyll's cycle, and speed up curing.

With that said, chlorophyll is, in fact, the number one reason of harsh smoke or chemical taste. **Chlorophyll naturally breaks down*** as the nutrient uptake slows (also naturally) after it's lifecycle comes to a complete end. This is witnessed in nature all the time on all manner of flowers and trees.
The act of Flushing, for better tasting bud, is a complete waste of time.

NPK has nothing to do with smoke quality.

The best explanation of why people forcefully withhold nutrients is to break the internal chemical chain of events within the chloroplasts, hence slowing or stopping the chlorophyll from being produced. Yes, this does happen, and Yes, your smoke may be smoother. But know this.... withholding nutrients he last week's before harvest, you're more than likely going to limit the full potential growth of your plant. Withholding nutrients is not the reason for better tastin and smoother smoke, broken down chlorophyll is.


Why anyone would want to hinder growth and yield for a week or two of time curing is beyond me. Why not just cut early, right? Why not quick dry, right? Heres an idea, if youre gonna spend all that time and money to grow, why not do it right, grow it right, feed it right, dry it right, cure it right, and not take shortcuts. Again, just an idea.


PS, anyone with a curious mind interested in learning more about the chloroplast within cannabis, here's a short clip on it. Expand your mind...., cheers.

Dumme said:

From my understanding, "Flushing" or "to Flush", as defined by google is:
cleanse by causing large quantities of water to pass through it.
"flush the toilet"

DWC can't be flushed, as you just dump the water and refill. When the term is used in growing Cannabis, it's for cleansing Soil.

People are confused as to "Flush" by cleansing soil, and to "withhold nutrients" at the end of Flower, to break the Chlorophyll's cycle, and speed up curing.

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Well I agree that you can't flush swc like you do soil obviously but alotbof people flush DWC maybe it's not the correct term but it's definately happening. Thanks for helping me understand the Google definition of flushing though never know when that may come up

Pat666 said:

Well I agree that you can't flush swc like you do soil obviously but alotbof people flush DWC maybe it's not the correct term but it's definately happening. Thanks for helping me understand the Google definition of flushing though never know when that may come up

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Why do you think the term "Flushing" was used? The term originated from a soil grower whom had problems with salt buildup and consequently the wrong nutrients.

How do you link cleansing soil to dumping water in DWC?

In hydro or dwc you should be flushing personal preference. Flushing in dwc is shorter because it's hydro. And cleaner tastier burning smoke is a must. I flush using flawless finish. First 3 days with water and final flush the the last 3 to 5 days is pure clean water. And the science behind short version is when you have no more nutrients in your water or reservoir then your plant with start to consume the nutrients out of the media whether it's hydroton rock or Rockwell or coco. Then once the nutrients are all gone from the media the plant then take the nutrients from its leaves. Thus the browning of the leaves during a proper flush. So if you think about it your not cutting off feeding to your plant your just forcing it to use the nutrients in the media then in the leaves. Nothing is worse them getting a bag of beautifully buds and then cough your assistance off and have a sore throat or shitty tasting pot. So if it really doesn't matter then why do some people swear by it. Some day when science and enough funding go into cannabis like advanced nutrients does then we will know all our answers soon enough with proof behind it

BusterVAP said:

In hydro or dwc you should be flushing personal preference. Flushing in dwc is shorter because it's hydro. And cleaner tastier burning smoke is a must. I flush using flawless finish. First 3 days with water and final flush the the last 3 to 5 days is pure clean water. And the science behind short version is when you have no more nutrients in your water or reservoir then your plant with start to consume the nutrients out of the media whether it's hydroton rock or Rockwell or coco. Then once the nutrients are all gone from the media the plant then take the nutrients from its leaves. Thus the browning of the leaves during a proper flush. So if you think about it your not cutting off feeding to your plant your just forcing it to use the nutrients in the media then in the leaves. Nothing is worse them getting a bag of beautifully buds and then cough your assistance off and have a sore throat or shitty tasting pot. So if it really doesn't matter then why do some people swear by it. Some day when science and enough funding go into cannabis like advanced nutrients does then we will know all our answers soon enough with proof behind it

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You don't flush "Water", you flush "Media" with water. Please understand the difference. The is key; in some DWC Hydroponic systems, there's hydroton or alike. It's possible to "Flush" the hydroton, not DWC. Hydroton is used to essentially hold the plant, and is not necessary as it can be exchanged with foam or any other substances. Again, DWC is water so it's impossible to clean water with water.

There's absolutely no credible evidence supporting a "cleaner tasting burn", by doing it.

You misunderstood what I was trying to say or I wrote it wrong. Obviously you don't flush water. You use the water to flush media. Pretty sure that's what I posted. And from personal experience I prefer flushed properly cannabis. Majority of cannabis connesuers would or use organic nuts and even then you should always be doing a flush. If I was here to make money on cannabis then I would throw flushing right out the window who cares btu this is personal smoke and I want the best of the best that I can produce. Anyways no need to respond I'm not here to argue you obviously don't see anything behind flushing. But all good personnel preference. Cheers