DWC flushing: why use pH-corrected water?

Forgive me if this is a dumb question, but when I read about flushing in DWC, people say to use pH-corrected water (I presume this means 5.8 ). I don't really understand why normal tap water (mine has a pH of about 7.8 ) wouldn't do. The whole point of pH-ing, I thought, was to make sure your plants can absorb the nutrients from the nutrient solution. Well, when you're flushing, they're not to absorb any nutrients, but rather use up the energy stored in the leaves, right? Can someone please explain this to me?

I use grape koolaid to flush! it comes ph'd.
But seriously I've asked myself that same question before which then leads to why flush at all which then leads to hell yeah, flush with grape koolaid. you know what I'm sayin?

I do an RO water flush after I chop. Twelve hours of light, Twelve hours of darkness. I started this years ago using mountain spring water to make the homegrown more tasty.

flat9 said:

Forgive me if this is a dumb question, but when I read about flushing in DWC, people say to use pH-corrected water (I presume this means 5.8 ). I don't really understand why normal tap water (mine has a pH of about 7.8 ) wouldn't do. The whole point of pH-ing, I thought, was to make sure your plants can absorb the nutrients from the nutrient solution. Well, when you're flushing, they're not to absorb any nutrients, but rather use up the energy stored in the leaves, right? Can someone please explain this to me?

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I don't flush much anymore, but when I did my tap was around 7.2 and after I added the flushing additive my PH would be around 5.8..I change my nutes once a week so I don't believe there is much build up of salts..Maybe it is more for the dirt grows?..I only flush at the very end for maybe two days if at all....hope this helped...nitro.

From my understanding, there should be no need to flush in dwc

I have argued this many times over the years, correct, there is absolutely no need to adjust pH in flush water or a hydro cloner.

If you have given your girls a hard ride and they are looking a bit shabby then flushing in dwc is a good thing, honestly though if you start reducing your strength earlier there should be no need to flush. Phing...flush BAAA! Phing cloner water...BIGGER BAAA! No need. JAS

You are correct, ph is for nute uptake... anything you do that doesn't revolve around nute uptake does not have to be at a specific ph.

No need to explain, you got it right. my water also comes out of the faucet at 7.8. Besides, i only flush anywhere from a couple hours to a couple days tops before harvesting. I never bothered to adjust it because the plant never even sits in that water for long. You're about to kill it anyway, know what i mean. The only reason i flush is because I noticed the ppm of my tap water goes up when u leave a plant in it. I assume it's just the extra nutes left in the plant draining out. I left one in the nute water this time around and marked it just to see if i even notice a difference. All the same strain purps x white Russian. Never read or heard of anyone else with that cross. We call it Candy. Always wondered if it's been done and named already.

Thanks everyone. I had just had read over and over again "I use pH-ed water to flush" which didn't make any sense to me.

Also, great to read that with the RDWC I'm running I don't need to run the flushing for too long. I'm about near my flush time and chop date on my autoflower grow (running Dutch Passion Think Differents on day 83), so this was coming up soon.