PH Down - Why do I need so much for WELL water, but literally drops for RO

[Budley Doright]

I add 30 ml of 35% sulphuric acid to 100 litres (yes lots) but once it’s set it stays there. I struggled when I first started by adding drops and bringing it down only to have it go back up and as stated my choice of nutrients had a big effect on stability as well. Never found silica to do much either so stopped spending money on it lol.

 

[Michael Huntherz]

Silicates are so pointless.. How about feeding plants what they actually want. Crock nutrition... (still waiting to see what a silicon deficiency looks like)

Fuckin A dude, just had a conversation about that yesterday. My friend ended up saying “you must be dumb, if you can’t see the difference, I didn’t think you were dumb.” And I said “yep I am an idiot, dabs?”

Pseudoscience and magical non-thinking abounds.

 

[jarvild]

Considering silicates are a part of of the composition of soil make-up in nature to varying degrees. What's the harm in it?

 

[Michael Huntherz]

Considering silicates are a part of of the composition of soil make-up in nature to varying degrees. What's the harm in it?

No harm in adding marbles to my media, either, but also no point.

Refuting appeals to nature (rhetorical shit-tactic) and the naturalistic fallacy (an especially shitty form of the is-ought prblem) is becoming so tiresome to me, we collectively need to stop thinking of the natural world as “good” or optimal by default.

Think better.

 

[NanoGadget]

There are benefits to Si in plant biology. Strengthening of cell walls, greater drought resistance, greater tolerance to heavy metal exposure (see the paper
'Importance of Silicon and Mechanisms of Biosilica Formation in Plants' by Mahbob Sahebi et al).
The main reason it's typically not needed is that most soil has plenty of it to begin with. Even in hydro most plants will do fine without it, but that doesn't mean there would be no benefit to supplimenting with small amounts of it.

 

[Roger A. Shrubber]

silica is kind of pointless if you're growing in soil. soil-less and hydro can get some benefit from it, but it's not a major nute, a little bit once or twice in veg ought to be enough for the plants whole life.

 

[Roger A. Shrubber]

"No harm in adding marbles to my media, either, but also no point."
this would actually make your media drain worse, water has a hard time transitioning from small particles to larger ones, has to do with surface tension. thats why it's actually a bad idea to put stones or pot shards in the bottom of your pots. they'll drain better right off the bat, but as the medium fills in the gaps in the stones, it will drain worse and become a wet zone

 

[Michael Huntherz]

"No harm in adding marbles to my media, either, but also no point."
this would actually make your media drain worse, water has a hard time transitioning from small particles to larger ones, has to do with surface tension. thats why it's actually a bad idea to put stones or pot shards in the bottom of your pots. they'll drain better right off the bat, but as the medium fills in the gaps in the stones, it will drain worse and become a wet zone

Fair points all. You are right.

There are benefits to Si in plant biology. Strengthening of cell walls, greater drought resistance, greater tolerance to heavy metal exposure (see the paper
'Importance of Silicon and Mechanisms of Biosilica Formation in Plants' by Mahbob Sahebi et al).
The main reason it's typically not needed is that most soil has plenty of it to begin with. Even in hydro most plants will do fine without it, but that doesn't mean there would be no benefit to supplimenting with small amounts of it.

I enjoyed this paper a lot, thanks for the enlightenment.

Refuting appeals to nature (rhetorical shit-tactic) and the naturalistic fallacy (an especially shitty form of the is-ought prblem) is becoming so tiresome to me, we collectively need to stop thinking of the natural world as “good” or optimal by default.

Think better.

I am an asshole, much of the time, I can and will be wrong; but I stand by this part.

 

[Roger A. Shrubber]

i don't like when people say they're trying to replicate nature in their grow rooms. you can't do that...so why try?
you have some advantages in a grow room, use them to your fullest ability. no matter how powerful your light is, it's never going to be the sun. but, plants in nature have to take whatever nutrients are available to them and do their best with it. you can make sure they have everything they need. you can make sure they always have enough water, but not too much. you can keep pests out, and get rid of any that do get in, in a timely fashion. you can make sure they never get too hot or too cold....none of which happens in nature....

 

[NanoGadget]

Fair points all. You are right.


I enjoyed this paper a lot, thanks for the enlightenment.

I am an asshole, much of the time, I can and will be wrong; but I stand by this part.

I definitely agree with your last paragraph and agree wholeheartedly. People often assume nature = optimal and very often, for our purposes, that is simply not true.

 

[Dr. Who]

Silicates are so pointless.. How about feeding plants what they actually want. Crock nutrition... (still waiting to see what a silicon deficiency looks like)

This is SOOO right!

There is absolutely NO reason to use any form of silicate in soil grows....period! The plant takes ALL it needs from the soil it's self!

 

[Dr. Who]

There are benefits to Si in plant biology. Strengthening of cell walls, greater drought resistance, greater tolerance to heavy metal exposure (see the paper
'Importance of Silicon and Mechanisms of Biosilica Formation in Plants' by Mahbob Sahebi et al).
The main reason it's typically not needed is that most soil has plenty of it to begin with. Even in hydro most plants will do fine without it, but that doesn't mean there would be no benefit to supplimenting with small amounts of it.

In hydro yes....In soil? All your doing is screwing with the balance of available forms of Calcium.....In soil, it can limit Ca by chemical changes to the Ca.
Small amounts, yeah, can pass but, the point is why? Your supplying NOTHING that the media is already able to, and at OPTIMAL levels too.

Not to mention the potential pH changes it makes in the soil, over time by build-up.

 

[Dr. Who]

Look, Not much about the actual body of the OPs question is there?

Tap or well water contain minerals. Mostly in the form of Calcium compounds but, with varying amounts of the others (compounds). Some can be too "overpowering" in some and cause imbalances and growing problems.

It has been widely accepted for some time that 150 ppm is the benchmark limit for dissolved solids in water to be used for any controlled growing!
These dissolved solids in the water are called "buffers". These are mainly , like I said Ca compounds.

RO removes all, to almost all "buffers" or dissolved solids from that water. This makes it hard to balance any pH value by RO use, over a given time by not having those buffers to hold that value.
What has not been said is that a major contributing factor to RO pH is the amount of dissolved Co2 in that water also...We don't really control that. We simply add a buffer and go from there.

The idea of RO is to start with nothing as far as ppm is concerned. YOU now have the ability to set your "buffer" level and add the desired nutrient mix to balance the amount or % of each nutrient. Whether it be a Macro nutrient or a Micro nutrient!
Complete control is now at your fingertips. YOU need to know how to best employ that..

So then, this water, stripped of it's "buffers" is now lacking the needed Ca and Mg found in "normal" waters. To simply buffer RO. The basic value given is a Ca/Mg compound at 5ml per gallon.
I prefer to use Ca Carbonate based Ca/Mg's to work better AS a buffer, yet still supply the plant with enough Ca to grow properly.

After this point. You now have a "clean" buffered water that you can add nutrients to, to supply a consistent and predictable growth response by the plant. This makes it far more easy, to to get run to run accurate consistency!

I do this. For just that reason...I want the same results. Run to run, with less nutrient use too!

RO is also known for better plant use of the amounts of nutrients used. You simply don't have all that extra "whatever" in the water, taking up effective nutrient space in that water. This allows the plant more efficient use of the nutrients you supply it.

Understand better now?

 

[NanoGadget]

In hydro yes....In soil? All your doing is screwing with the balance of available forms of Calcium.....In soil, it can limit Ca by chemical changes to the Ca.
Small amounts, yeah, can pass but, the point is why? Your supplying NOTHING that the media is already able to, and at OPTIMAL levels too.

Not to mention the potential pH changes it makes in the soil, over time by build-up.

Yeah, that's why I specified that it is pointless in soil. I would add a little to my reservoir every 2nd or 3rd res change when I was running hydro and would skip cal mag when adding Si as they don't tend to play well together.
I do think it is noticeably beneficial in hydro though and typically gets ignored.

 

[churchhaze]

It's pointless in hydro too... (still waiting for someone to show what a silicon deficiency looks like)

I would add a little to my reservoir every 2nd or 3rd res change when I was running hydro and would skip cal mag when adding Si as they don't tend to play well together.

So you'd skip 2 macro nutrients in favor of something that's not used at all... Nutrient ADHD.

 

[churchhaze]

Considering silicates are a part of of the composition of soil make-up in nature to varying degrees. What's the harm in it?

Aluminum is also a major part of the composition of soil.

 

[jarvild]

Aluminum is also a major part of the composition of soil.

So It's bad that I use a potassium silicate ? Even if I'm using it for the K more than the silicate.

 

[churchhaze]

So It's bad that I use a potassium silicate ? Even if I'm using it for the K more than the silicate.

In that case, why not use potassium nitrate? (13-0-44) or potassium hydroxide (0-0-84) if you want pH up

 

[jarvild]

Then your talking about making stock solutions. And I'm not talking K for a pH up use.

 

[Michael Huntherz]

So It's bad that I use a potassium silicate ? Even if I'm using it for the K more than the silicate.

I would not say it is bad, myself. Maybe beneficial, maybe pointless, and we all have our reasons. Never heard of potassium silicate, but I am not much of a chemist. Cheers