what i meant was PPM meters use conversion factor to estimate ppm from conductivity. conductivity is a more accurate measure. so water conductivity of 798 microseimens/cm is equal to 400-550 ppm depending which conversion factor your meter uses.
I highlighted that sentence in your quote as that is what I was getting at. The RO filter strips all minerals from your water, (also harmful things like lead and other heavy metals, pesticides, etc), and gives you a blank slate to engineer your own nutrient profiles with. The RO water doesn't 'strip' anything itself.
Hm, maybe I’m just confused but...using plain RO water won’t remove minerals from the soil? In other words, if I took a pot of FFOF potting mix and started pouring RO water, would the PPM level stay constant? no matter the amount of water I put in?I highlighted that sentence in your quote as that is what I was getting at. The RO filter strips all minerals from your water, (also harmful things like lead and other heavy metals, pesticides, etc), and gives you a blank slate to engineer your own nutrient profiles with. The RO water doesn't 'strip' anything itself.
In the case of true organic growing, not my forte, all the plants needs are built into the soil and just water need be added. If the soil is done right it's all there and nothing need be added to RO water to compensate for it's lack of minerals.
With quality hydro nutes all the plant's needs are in a few bottles including Ca and Mg tho maybe not in enough quantity for plants being grown in the intensive manner that indoor pot is usually grown in. In that case the addition of CalMag is a good idea tho I use less than half the recommended amount and have never seen a serious lack of either nutrient in my plants.
I started growing pot in DWC in 2001 and for at least the first 10 years never saw deficiencies in Ca or Mg and often never changed nutes for the whole grow. Wasteful as hell to change nutes for at least the first month or until switching to flower imeo. I used RO water only with AN 3-part nutes, no CalMag but some Epsom Salts.
I'm not looking for an argument either. I initially asked about the stripping in case I was missing something and thought that statement could use a little clarification.
I agree that flushing before cropping is another myth but it does have it's uses at times.
When a soil is too hot flushing extra water through can reduce the nutrient levels enough that the plants can handle it. Or like I do with soilless and hydro nutes if I see burning starting after a feed or screw up and overdose the plants it'll do the same as with soil. Get the nute level down to stop the burning.
Even with DWC I don't remove all the nutes at the end but remove half or so and replace with RO to lower the levels a week or so before I begin to crop. I'll take the big ripe colas first then leave the smaller stuff for around 10 days to ripen up some more and hopefully put on a bit more weight before finishing the job. If in soilless I'll just give them RO for the last week or more before cropping in the same way. I try not to overfeed so there shouldn't be enough left to worry about. I want to see the lower leaves begin yellowing near the end as that indicates the buds are stealing nutes to finish up with and I've not overfed.
Yep. The RO isn't adding any ppm if it's pure. Same with distilled water. Neither have a real pH of their own so always pH it after adding all nutes or if just watering just pour it in. It will not affect whatever the pH is in the soil.
This whole time, I thought minerals could be washed out of the soil haha. So then what's the science behind flushing? If minerals can't be stripped/removed then why do PPM levels drop as you pour more water?Yep. The RO isn't adding any ppm if it's pure. Same with distilled water. Neither have a real pH of their own so always pH it after adding all nutes or if just watering just pour it in. It will not affect whatever the pH is in the soil.
Except when soil is dry the pH goes up or down a bit but I can't recall which so wetting it will bring it back to what it was.
The only way it will 'strip' nutes is if you get runoff and remove that. Give that to another plant as feed if you want.
If I'm growing in actual soil organically I will use some of my dugout water to inoculate the soil with bacteria and fungi. We just filter the water but no sterilization and little fish and frogs live in there and we had 4 pairs of ducks nest in there this summer. Water should be teaming with healthy stuff for plants.
It's a good size. 82x52yds and 12ft deep.
That sounds pretty good. A lot of well and tap water has minerals in it that are great for plants but when you are watering with high ppm water all the time there ends up being too much and buggers up the plants.
As I said in the last post . . .
So if you wash the water thru the rootball it will dissolve nutrient salts, (minerals), and come out as runoff. If you remove the runoff then you reduce the amount of nutes in the rootball. That's what flushing does and if things are really going sideways with plants then it can often save them. I've seen rookies post, Help I just realized I fed my plants 10x the amount I was suppose to. What do I do!!!!!!!
yes if you get your water to below 200 ppm you can add cannabis nutrients at a quarter dose
Awesome thanks mate!
Science?? This is a weed growing forum, very little science involved
lol
Maybe get something that screws into your faucet and then draw off & store several 5 gallon buckets as needed? I know you're sick of hearing it but damn! Never heard of ppm that high coming out the tap?!
