RO water and buffering

[bluter]

Adding 50-100 ppm, do u believe it should be potassium heavy, ie, GH bloom heavy? Or more equal amounts to add up to 50-100?

the lowers might still pull some n in and green up a bit, but yes they would move to a flower / bloom nute. they aren't that far from finish. idea is just to get them there as nice as possible. it doesn't have to be pretty. you have a good run going.

i wouldn't do just pk, they still need / use n in flower, and you're bringing them back a bit. i never ever run a booster alone, and i don't usually run a booster at full strength. i make some head room in the regular nute sched and add it in.

if base nutes can't do a decent job alone, then drop the line entirely.

Bluter will give you more cogent advice soon, let's hope. Until then, the screenshot here shows the amounts of chemicals that are some of the GH products. If you scan across the line for "K", you'll see how many PPM of K are in a given fert. Not a lot, eh? Adding even 50PPM worth of K could cause a serious imbalance, AKA "lockout".

One warning - I don't think there's any evidence that "bloom nutes" actually do anything for cannabis. You might check out this thread for a perspective on that. Full disclosure - I've drunk the Koolaid. I uses dry ferts, same mixture from seed to chop.

holy shit. i don't think i'll ever be more cogent than that chart.

 

[Bill284]

Adding 50-100 ppm, do u believe it should be potassium heavy, ie, GH bloom heavy? Or more equal amounts to add up to 50-100?

Sorry I'm late.
I'm frozen from working outside.
I redid the door on the new grow room.
You seem to bother ok on ph? Now right.
That garden I'd be feeding at least 1200 ppm.
Are you only at 700?
sorry if I'm out of line.
You seem to be taken care of.
Hope you are well.




#Vivosun #Love What You Grow
Bill284

 

[H20gro]

Sorry I'm late.
I'm frozen from working outside.
I redid the door on the new grow room.
You seem to bother ok on ph? Now right.
That garden I'd be feeding at least 1200 ppm.
Are you only at 700?

Ph is just dropping slowly and i was under impression it should be rising as nutes are used. I had a lockout issue right after stretch and have been babying her since. Went to ro water for first time after lockout so im teying to dial in the ph issue w it.

But yeah im only at 700 bc ive been gradually increasing since lockout. Scared to go too high and burn her up.

I do believe the lockout was from extra hard tap water (450 ppm) and not flushing/swapping res. Plus i added a strong dose of nutes atop the unflushed water. So maybe sunday i will try a 1200 ish mix. Straight ro water vs tap at 1200 could make a difference

 

[bluter]

That garden I'd be feeding at least 1200 ppm.

you know it's dwc right ? i confused it with coco earlier. a lot of dwc / rdwc tops in the 900 - 1000 range.

 

[Delps8]

holy shit. i don't think i'll ever be more cogent than that chart.

Lotsa numbers there but no advice. I can do the research and pull up the data but, as I found out a couple of years ago when the WonderChart took me in the wrong direction, that's not expertise. Experience helps a grower know what's germane to a particular problem and then, using knowledge of the underlying subject matter, determine potential courses of action to follow.

With only 5 grows under my belt and growing just a few plants in a bathtub-sized res, my experience is, frankly, quite limited. That's why I appreciate the contribution that folks like you make (and I see that @Bill284 has joined the party).

 

[Smokey0418]

I was wondering aloud earlier if i should increase nutes concentration to affect ph dropping.

@bluter

As feed comes out of the water ph goes up , so no .

Once you get on to it ph can become very stable.

If your roots look clean and not carrying and crap on them , then I would say your feed is too high.

Ph drops for rot and feed being to high on established plants, imho.

Good luck with your grow.

 

[H20gro]

As feed comes out of the water ph goes up , so no .

Once you get on to it ph can become very stable.

If your roots look clean and not carrying and crap on them , then I would say your feed is too high.

Ph drops for rot and feed being to high on established plants, imho.

Good luck with your grow.

I do recall reading recently, now that uou mention it, that theres an inverse relationship between the two, ie, too strong and ph drops while too weak ph rises.

Which brings me to another thread i started recently, and i dont believe you commented there, @Smokey0418 , so id like your opinion on my original problem. I was using tap water at 450 ppm and after stretch things got wacky. Ph was rising as soon as it went in bucket. I would ph the tap water to 6, pour it in and pump simultaneously…. The water coming out would be over 7.

Ive since gone to ro water but am perplexed by the instant rise in ph at that time.

 

[Smokey0418]

When I look at your plant I have another ?
What exactly do add to your ro.
Your ec at 1.2-1.4 should not be far off.
Thank you.

 

[Smokey0418]

I do recall reading recently, now that uou mention it, that theres an inverse relationship between the two, ie, too strong and ph drops while too weak ph rises.

Which brings me to another thread i started recently, and i dont believe you commented there, @Smokey0418 , so id like your opinion on my original problem. I was using tap water at 450 ppm and after stretch things got wacky. Ph was rising as soon as it went in bucket. I would ph the tap water to 6, pour it in and pump simultaneously…. The water coming out would be over 7.

Ive since gone to ro water but am perplexed by the instant rise in ph at that time.

450 ppm is a lot of something in the water.
Like the bottles spring water for example is 220 , had label with what’s what. Calcium and magnesium included.

I know what some would say and that’s to add your fertilizer right on top , which is doable.
But I would be a bit Leary on wth is the 450 , sulphur, iron, cal and mag , sure but how much .
You would have to test and see.
Good project since your in separate pails before you get a much bigger one in rdwc.

So me , it’s ro and I just calmag it up and add my nutes according.

 

[Smokey0418]

For example now, I have smaller plants were roots are just getting established.
Yes they were cuttings but I would also treat smaller plants very similar.
I start with 180 ppm of calmag then the a&b I use to 500ppm for 1ec.
At two weeks from planting I have roots in the water and my ph drops . 3-.5 over 12 hours .
I have even had it more violent and it’s dropped 1.
I would most definitely just ph it back up, or better yet use a small amount or silc , 2ml will raise my 35-40 gallons . 5 and seems to hold it better.
I can read my ppm and see it drop 20-30 and from other grows I know I’m close and once I get more root that will stop.

Then would go into flower maybe going as high as 1.4 but again I would monitor the ppm and adjust how they tell me.

 

[H20gro]

When I look at your plant I have another ?
What exactly do add to your ro.
Your ec at 1.2-1.4 should not be far off.
Thank you.

When i was using tap on this plant, i was using 1/4 strength GH 3 part, no cal mag. Since the lockout issue ive used ro water w calmag, and GH 3 part flora. I also have tried mixing ro w tap but am now understanding it may not be good. So, i know the plant looks a lil tired but shes been in intensive care for a month or so and hasnt declined in health. Just kinda maintained…

 

[Bill284]

When i was using tap on this plant, i was using 1/4 strength GH 3 part, no cal mag. Since the lockout issue ive used ro water w calmag, and GH 3 part flora. I also have tried mixing ro w tap but am now understanding it may not be good. So, i know the plant looks a lil tired but shes been in intensive care for a month or so and hasnt declined in health. Just kinda maintained…

If you put calmag in first, then follow the chart for the flora nova series you shouldn't have issues.
But there are a lot of other factors in dwc, temp, ph....etc.




#Vivosun #Love What You Grow
Bill284

 

[H20gro]

Operating under the assumption that too strong nute solution can cause ph to drop in dwc, ive brought the solution from 700 to 500 and ph at 5.8. Stay tuned for what happens tonight at 6! Hopeful ph remains close or even rises!!

 

[Bill284]

Operating under the assumption that too strong nute solution can cause ph to drop in dwc, ive brought the solution from 700 to 500 and ph at 5.8. Stay tuned for what happens tonight at 6! Hopeful ph remains close or even rises!!

As the nutrients circulate the saltsxwill drop out.
This will cause a decrease in ph.
That's going to happen no matter what
Maintaining ph and nutrient temp is a daily requirement IMO.
Hope you are enjoying your weekend.
Take care.




#Vivosun #Love What You Grow
Bill284

 

[Peat Phreak]

Add 100-200 ppm of potassium carbonate to RO for buffering

https://scienceinhydroponics.com/2020/05/understanding-the-carbonic-acid-bicarbonate-buffer-in-hydroponics.html

 

[H20gro]

Bluter will give you more cogent advice soon, let's hope. Until then, the screenshot here shows the amounts of chemicals that are some of the GH products. If you scan across the line for "K", you'll see how many PPM of K are in a given fert. Not a lot, eh? Adding even 50PPM worth of K could cause a serious imbalance, AKA "lockout".

One warning - I don't think there's any evidence that "bloom nutes" actually do anything for cannabis. You might check out this thread for a perspective on that. Full disclosure - I've drunk the Koolaid. I uses dry ferts, same mixture from seed to chop.

So go lightly if not without bloom nutes altogether is what youre suggesting? I have to admit im missing the point if this chart and am confused by you saying “not a lot” of k. I appreciate any and all help, just talk to me like a 4yr old and eventually i will get it.

 

[Delps8]

So go lightly if not without bloom nutes altogether is what youre suggesting? I have to admit im missing the point if this chart and am confused by you saying “not a lot” of k. I appreciate any and all help, just talk to me like a 4yr old and eventually i will get it.

That's a screenshot of a spreadsheet that calculates the PPM's of the chemicals that are in the different commercial products that are listed across the top.

Find the row for "K" and scan across the line - 13, 139, etc. That's how many PPM are in a gallon of that particular nutrient. The highest value is 139 PPM so if you drop in about 50 PPM of K, that's a huge percentage change in the amount of K in the res.

The ferts in the picture are the only ones listed in my copy of the spreadsheet and I know nothing about them, frankly, I was just using the data in that part of the spreadsheet as an example.

One key item to remember is that one of the characteristics of hydro is that things can happen very quickly, far more quickly than in soil, so it really does pay to "measure twice, cut once".

Another piece of it is that a lot of growers spend a lot time changing thins in their nutrient mix when, one, there's probably no need to and, second, what they're doing is, at best, of no value and, at worst, causing problems. I think it's a tendency of the people who are attracted to this hobby. I'm not knocking it, certainly. It's part of what makes a lot of us tick and it's something that spur us to ask "Am I doing this for me or for the plant?"

I don't know/recall if your plants actually had a K def but, if so, per the two paras above, "tread gently".

 

[Cannabist1]

Ok, chemistry came along in high school about the same time as cannabis for me. So i chose the more hands on, experimental branch of the science, ie, smoked weed and didnt pay attention in class so please help me understand how to get ro water “stable”, especially regarding ph.

Ive been told to mix it with tap water and/or to use both ph up and ph down (buffer?).

As it is now, my dwc plant in week 8 of flower seems to have water ph dropping unless i add tap or ph up…. Even then it seems to slowly drop. Ideally it would rise as nutes are used i thought.

Anyway, help understanding this and ideas to approach ph “stability” w ro water would be greatly appreciated.

I am new to ro water and still learning..

Tia

@bluter @Delps8 @Bill284 @OGpapa

I’m in the same boat, except I’m still stuck on soil. I can’t get away from the fact that Cannabis cleanses it.

I started using RO my second grow but I gave up on it because I was too busy with work and my knowledge with adding nutrients back wasn’t sufficient enough.
I know RO is stripped of pretty well all minerals so I was doing the 1/2 “dechlorinated” tap method for a bit; along with adding the usual Veg, then Bloom nutrients and other sourced minerals depending on the stage. One product I haven’t tried is CalMag, which I constantly see new guys talking about like it’s the best solution in the World.

With all that being said, the bud turned out airy, I said screw it and switched to just tap water my next grow.

Any comments on adding minerals and nutrients to RO for soil?
Thanks guys

 

[bluter]

Any comments on adding minerals and nutrients to RO for soil?

generally don't do RO for soil but it depends on what you call soil. where i live it's recommended to use RO for anything except LOS or outdoor growing.

 

[Cannabist1]

generally don't do RO for soil but it depends on what you call soil. where i live it's recommended to use RO for anything except LOS or outdoor growing.

Anything is possible my friend. It’s indoor. Manure, coco, perlite, old potting soil mix.