To RO or not RO

[sopappy]

readin' how to make my cartridges last longer.... dudes are telling me there can be lots of CO2 in water and it's hard on the DI cartridge.
I'm thinking it's going to be hard on roots too, but I've never heard of this in mj growing.

oh, cartridge life fix is to install a tub and bubbler after the membrane and let gravity feed the DI cartridge below it.

 

[sopappy]

Thanks duck, saves me having to read up and mess with buffers.

Guess I better think about replacing filtres and cleaning the rig. I've since discovered my city water uses Chhorlamine instead of Chlorine. I read it's the carbon filtre that takes out the chlorine. If I use a chloromine filtre, do I still have to use the carbon one as well or can I just replace it w/ the chloromine one?

 

[The Hemp Goddess]

Is your water high enough in ppms to justify an RO or are you just dong this because of the chloramine?

 

[sopappy]

City water is fine at 50-70 but I've been having trouble so I thought it might help. I also use it in my humidifier (instead of rip off filtres) and drink from a tap before the de-min cartridge.
Then I find out we don't use chlorine and I don't like what I read about chloramine and plant life so easiest is to replace the carbon with the chloramine one.

 

[The Hemp Goddess]

If you don't have a lot of dissolved solids in your water, I'd go with a filter that removes chloramine--using an RO is overkill. I have a filter on my outside hose that removes chlorine, chloramine, heavy metals, and a few other things. I have well water, so don't need the chlorine/chloramine removal, but I do have arsenic in my water and need to filter that out.

 

[sopappy]

Overkill and pricey. Cartridges don't last more than a year or so and if you don't clean them, you can get some interesting bugs in yer gut, just read it somewhere, it does save a small fortune in those humidifier filtres though.
And look what I found for the chloramine, internet drives me nuts, popeye

Reverse osmosis. Reverse osmosis (RO) units of the type installed in homes usually have one or two activated carbon filters in the path to protect the RO membrane from chlorine and chloramine, which would poison it. RO-processed water is, therefore, chloramine-free,

I'll have to pick up a test kit, why do they have a chloramine filtre if the carbon one does it?

(ha, neighbour's A/C unit's compressor is coming on calling for cool when it's 65 degrees outside, wonder what he's growing in there)

 

[pcduck]

Bulk reef supply runs specials all the time.

 

[sopappy]

Bulk reef supply runs specials all the time.

18% surcharge to ship to ca but probably worth it, thanks

 

[stinkyattic]

If you aren't STORING your pH probe in RO water no need to worry about damage. It's only harmful when used as a storage solution (use buffer 4 instead). And there's really no point in testing the pH of RO/DI/distilled water anyway as the ionic strength is so low as to give long stabilization times and wonky readings. Test /adjust your pH as the last step after you've added all your fertilizers and supplements.
When using any purified water, including rainwater, the very first step is to add CalMagPlus or comparable mineral replacement. Likewise, if your tap water is very soft to begin with, you are fine using the CalMag to bring up your base EC. Do this before adding other ferts, and simply repeat at every reservoir dump.
An RO or IX system makes sense primarily for hard water over about 125ppm TDS (as a comparison, the city water where I work as a WWTF operator comes in at about 45ppm as NaCl equivalency, this is pretty average) , or water that contains a high level of organic acids such as tannins.
Before investing in a purification system, be sure you can justify buying it!

 

[Socrapy]

Freaky, why does this hit only happen when yer stoned?
I came here after searching RO and find my own thread a few day after stinkyattic responds to a year old post.
I friggin' gave up soon after that post, seed problems, fighting the bugs and the root rot, tried organic and all that "super" soil is in my backyard now, makes for great grass

I had to get away from it, been buying fromk BC... had some Rockstar one day last week and I dug up my hydro stuff and am starting again, seeds sprouted today,
so I'm prepping the tank, ebb and flo
but I'm still hung up on the chloramine and I stumbled across something intriguing.
To wit:
Acidification. It is also possible to remove chloramines by lowering the pH of the water. At low pH monochloramine converts to dichloramine, which clears overnight. ) Reducing the pH of the water to near pH 4 will allow the dichloramine to escape; you could then restore the pH to a higher value

What's the harm in dropping the pH to <4 wait a day, bubbling all the while, then add nutes and pH to 6.1

 

[stinkyattic]

Aww shoot, my bad, the thread wasn't very far down and it didn't even occur to me to check the expiration date on the carton lol.
Yes, dropping the pH with just a little phosphoric acid is totally fine, if you do it and then readjust BEFORE adding ferts. This a common and versatile method in wastewater treatment. Only thing to be aware of is that once ferts are added, pH <5 or >10 may be enough to break chelation in fertilizers and cause the ionic components to recombine into unavailable salts. So yeah, do your magic on the tap water as a first step!

 

[Socrapy]

Aww shoot, my bad, the thread wasn't very far down and it didn't even occur to me to check the expiration date on the carton lol.
Yes, dropping the pH with just a little phosphoric acid is totally fine, if you do it and then readjust BEFORE adding ferts. This a common and versatile method in wastewater treatment. Only thing to be aware of is that once ferts are added, pH <5 or >10 may be enough to break chelation in fertilizers and cause the ionic components to recombine into unavailable salts. So yeah, do your magic on the tap water as a first step!

I've responded to posts way older than a year, and I'm glad you did. Pleased to meet you.
I was going to pH lastly (for the first batch anyways) I'm afraid of over shooting the runway, 60L tub
should I aim for 6.5 ? as the nutes will cause another drop, hopefully get 6.0

what do you mean <5 or >10? what it looks like? 5.0 and 10.0 ? my metre's never gone higher than tap water 8.5

 

[The Hemp Goddess]

You should always pH your solution after you have added nutes.

 

[stinkyattic]

You should always *finalize* your pH adjustment after nutes. Absolutely! This is important and I should have mentioned it.

If you are pH adjusting your water to a level far, far outside the range fertilizers can stand before breaking down, for purposes of water pre-treatment, bring the pH back to the 5-9 range before adding anything else.
Fertilizers will chemically degrade outside of this range; above 10, the chelators will break down and the micronutrients (metals) will precipitate out.
At a very low starting pH, your fertilizer macronutrients will partially go into equilibrium as their respective acids.
Whatever you do to pretreat your water, reverse it prior to building up your nutrient mix.

 

[Socrapy]

You should always *finalize* your pH adjustment after nutes. Absolutely! This is important and I should have mentioned it.

If you are pH adjusting your water to a level far, far outside the range fertilizers can stand before breaking down, for purposes of water pre-treatment, bring the pH back to the 5-9 range before adding anything else.
Fertilizers will chemically degrade outside of this range; above 10, the chelators will break down and the micronutrients (metals) will precipitate out.
At a very low starting pH, your fertilizer macronutrients will partially go into equilibrium as their respective acids.
Whatever you do to pretreat your water, reverse it prior to building up your nutrient mix.

ahah, wasn't sure how to adjust BEFORE and AFTER, makes sense now... I'm leaving it sit overnight at 3.7 Tomorrow, I'll adjust to 5.0 ,then add nutes and adjust again

If I don't adjust to 5 first, I'll go into that equilibrium thing. Got it, thanks!

 

[Socrapy]

You should always pH your solution after you have added nutes.

Deja vu all over again... one of my first posts was on this. I read somewhere that once you know what your adjustment is (ie 3mil pH down), next time, you add the adjustment BEFORE the nutes, damned if I can remember why though

hey, miss... can you tell me what email provider sopappy registered under or is that private. I thought it was mail.com but nope.

 

[The Hemp Goddess]

I really don't understand pHing, adding nute, and then pHing again? What is the purpose of that? Why not just add nutes and then pH?

 

[stinkyattic]

I tried to explain it in my previous posts as best as possible without getting too deep into chemistry but I'll give the bullet points:
- fertilizers are stabilized for use in water that ALREADY has a pH not too far off from neutral
- the stabilizers are in a family of chemicals known as chelators. This includes EDTA, oxalic acid, and others, but these are the most common ones used in fertilizers. The word comes from the Latin chelos, which means claw. They essentially grab on and guard the form that the fertilizer chemical is in from reacting with other chemicals. Without going into a drawn out explanation of ions, simple molecules, chemical bonding, and salts, the chemicals in a fertilizer are held in a stable form that allows for uptake by plants.
- exposing chelators to extremes of pH will break them down and make them unable to prevent the fertilizers from dissociating into their component ions. For example, magnesium sulfate will dissociate into Mg+ and SO4-. Sulfate can further react with water to form oxygen and sulfuric acid but that is beside the point... the magnesium can form a hydroxide with the oxygen in the water and fall out of solution, where it is unavailable. This is just one example - the complexity of fertilizers means a chemical soup that, if not stabilized, will change drastically. And this is NOT reversible.
- tap water comes into your house in a safe working range and does not need to be preadjusted at all.
-if you are pre treating your incoming water by pH manipulation... just put it back the way you found it prior to adding fertilizer.

Source: I am an industrial chemist and licensed industrial wastewater treatment plant operator. And I began my career well over 20 years ago in a large commercial hydroponic operation growing basil, of all things. Now I just worry about pH adjusting industrial process tanks to precipitate heavy metals so that they do not pass through to the town sewer and kill off the good poop eatin' bacteria or harm the environment. I INTENTIONALLY use the technique described above with the GOAL of breaking chelation and allowing insoluble salts to form and be settled or filtered out as solids.

99% of growers don't need to worry about this. It only applies to someone attempting pretreatment using pH manipulation. Never expose fertilizers to pH extremes. Always do your final pH adjustment prior to feeding your plants.

 

[Socrapy]

I really don't understand pHing, adding nute, and then pHing again? What is the purpose of that? Why not just add nutes and then pH?

I trying to get the chloramine out of my water by dropping below pH of 4.0 (overnight)
Stinky is warning of scary chemical goings on if I add nutes below a pH of 5.0
so I have to bring it up a bit before adding nutes and adding the nutes will change the pH again so there's the final pH

once I know the numbers, I'll be able to add the exact amount needed at 5.0 stage so that the nutes bring it down to say 6.0 and I won't have to do that final adjustment

 

[stinkyattic]

You'd be technically bringing it up to 6, but don't be afraid of the final adjustment, that's the easy one since fertilizers are usually buffered and it won't take much. I keep my pH down/up in diner ketchup dispensers or other small orifice containers so I can just add a little squirt, mix, check, squirt, repeat until you get where you want to be. Also I ran my hydroton ebb n flow at 6.5 as the target. Don't be afraid of pH adjusting. It's an art, and the more you do it, the easier it gets!