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Chlorines effects on plants

RobFromTX

Well-known member
So I live somewhere the chlorine levels in the tap water are noticeably high. I mean you'd think its at the level of a public swimming pool. For the longest time now I've been filling up an igloo in the grow room with water for my plants as the research I've done online says it dissipates after a few days. But it is no less a pain in the ass to keep it full and I'm altogether tired of dealing with it. So I wanted to get some advice about chlorine's effects on plants as well as the soil. Is what I've been doing really that necessary for plant health? Would it really be such a bad thing to water them straight from the tap? Just wanted to get some other growers opinions on the subject as the research I've read online is very conflicting
 

shiva82

Well-known member
wo forms of vitamin C, ascorbic acid and sodium ascorbate, will neutralize chlorine. Neither is considered a hazardous chemical. First, vitamin C does not lower the dissolved oxygen as much as sulfur-based chemicals do. Second, vitamin C is not toxic to aquatic life at the levels used for dechlorinating water.
 

shiva82

Well-known member
the tap water is basically recirculating shit and piss water that has had a basic filtration and shit tonne of toxins added to kill bacteria. it is not ideal. get a rain water tank
 

mudballs

Well-known member
Veteran
Good RO's have limited gallon/litre output too...a big grow would require a big expensive unit or multiple units to support
 

Ringodoggie

Well-known member
I started having water issues when I moved to SoCal a few years ago. pH is about 8.5 and chlorine is super high.

I use a simple RV water filter. Different filters will filter various amounts of the chlorine. I think mine claims 80% reduction in chlorine.

I have always (and still do) fill 1 gallon jugs and let them sit. But I have this filter inline when I fill the jugs.

Cheap, easy and effective.


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mudballs

Well-known member
Veteran
In soil the chlorine molecule just can't make it deep enough to start to be an issue for the plant before it gets broken down. Maybe you hurt microbiotics but that's only top 1-2"
Now rockwool, etc. I would think it matters a whole lot, down to the very ppm for some elite setups
 

Dime

Well-known member
Can you try one plant from the tap and see how it goes? You can also put air lines in the holding tank to speed up the chlorine gas dissapation. They put enough chlorine into the tapwater to kill everything and sometimes it takes more and that's why it's stronger some days ,it depends on what they start with. You can buy chlorine test strips pretty cheap,if you go to the pool section at home depot I've seen them for free. You can call your municpality for support, they might be able to tell you about levels and answer your questions .If it's too high it will eat the taps and any steel so they don't go nuts.I use it right from the tap and haven't had any issues.
 

RobFromTX

Well-known member
Can you try one plant from the tap and see how it goes? You can also put air lines in the holding tank to speed up the chlorine gas dissapation. They put enough chlorine into the tapwater to kill everything and sometimes it takes more and that's why it's stronger some days ,it depends on what they start with. You can buy chlorine test strips pretty cheap,if you go to the pool section at home depot I've seen them for free. You can call your municpality for support, they might be able to tell you about levels and answer your questions .If it's too high it will eat the taps and any steel so they don't go nuts.I use it right from the tap and haven't had any issues.
Thanks for the heads up about that. I'll head to home depot this week and see if they have the strips
 

Veritas629

Active member
You should check whether your local water authority is using Chlorine or Chloramine. In short, chlorine is less stable and will dissipate by standing over night. You can help the process with an air pump or circulation of some kind. Chloramine is harder to gas off naturally. The easiest way to get rid of either chemical is to buy a bottle of Tap Water Conditioner from your local pet supply store. This product is used by people with aquariums, because the chlorine & chloramine are both lethal to fish. Water that is treated with this conditioner becomes safe for fish to live in nearly instantly after usage and I've always assumed the same for my plants. This stuff is also safe for the nitrogen fixing bacteria in an aquarium and I therefore assume it to be safe for beneficial microbes.
 

Rockchild

New member
So I live somewhere the chlorine levels in the tap water are noticeably high. I mean you'd think its at the level of a public swimming pool. For the longest time now I've been filling up an igloo in the grow room with water for my plants as the research I've done online says it dissipates after a few days. But it is no less a pain in the ass to keep it full and I'm altogether tired of dealing with it. So I wanted to get some advice about chlorine's effects on plants as well as the soil. Is what I've been doing really that necessary for plant health? Would it really be such a bad thing to water them straight from the tap? Just wanted to get some other growers opinions on the subject as the research I've read online is very conflicting
Here in Florida, my (tap) water is hard (390+Ppm) and they switch back/forth from Chlorine (when the need to flush the line or quickly bring down bad bacteria levels) to Chloramine. I Can tell you with 100% certainty that chlorine, nor chloramine will affect your plants. Indoors or out It’s ironic that years ago growers swore by a prod from DMT called “Zone”, which was just watered down Chloramine….
 

ojd

CONNOISSEUR GENETICS
Vendor
ICMag Donor
Veteran
In UK certain areas of UK water smells insane like a swimming pool as 1st post mentioned.

We use a product called neutralise in UK for soil/coco so chlorine doesn't kill beneficial microbes we use. We always used to leave for 24 hours back in day before using microbes but 24 hours only evaporates 1 of the chlorine not the other


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Ca++

Well-known member
Some other plants can be damaged by tap, but not many, and ours are a long way from that. Ours are hardy in this respect.

An inline filter will certainly reduce levels, but if our plants don't care, it might be a bad idea. You can run the same water through a brita, all day long, and see no EC decrease. What you will find, is the water gets more palatable to us, and more problematic for plants. Raised sodium levels and such, as the brita is an ion-exchange device. A water softener. You can cut one open and see the useful black carbon, and useless white ion exchange grains. Mixed about 50/50
You can just buy the appropriate filters. A couple of industry standard 10" housings is a good place to start. A pre-filter in one, just for particulates. A carbon in the second, protected by that pre-filter. We were using spun PP pre-filters, of 0.5um. That is so small, it raises an eye, and can lower EC. It's more likely you will find a 1um or even as big as 5um will do. It's just to prolong the carbons life.

If you buy an RO machine, you get the pre-filter. Followed by the RO element, that does nothing about chlorine. Then a carbon filter. It's what I just described, but low flow rate filters. Not 10" that will filter a garden hose, but thin push-fit pipework that might be easier to work with.

Amazon have a 10" filter cartridge here, that is a 5nm+carbon combination. For whole house flow rates. $15 each
A housing with some hose barbs might cost that again, but 99% reduction.


These are just the first I found. Not cheapest, and I didn't look at threads. Some 10" are not as fat as others, but it's straight forward enough. I will spend more time on this, for anyone that needs help.

Personally, I have been increasing the levels in my tank, not decreasing them. Some recent reading, tells me the US allows 1ppm in tap. That plants in general need under 2.5ppm. So we can see the gap between stinking and poisoning. A user here then spoke of giving 3.5ppm regularly. Someone then spoke about it not being very compatible with N, and I need to chase that up. The word neutralising was used.
 
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Ca++

Well-known member
Good RO's have limited gallon/litre output too...a big grow would require a big expensive unit or multiple units
I caused a big shift in the aftermarket cartridges we can buy. The manufactures of the cartridges have always sold a vast range, but the guys making the kits, chose a medium pressure high rejection cartridge. This seems reasonable, as some people really do have average pressure, and need really pure water. It won't be any of us though. Our pressure will be low, which means a mid pressure filter, won't deliver. We don't need water cleaner than rain either. Which is another demand slowing them down. They are chasing the wrong specifications for our needs. Many people spend big, making super pure, then mix it with tap because it's too pure. Remember most bottled feeds expect help from the tap. Not pure water. Then their is the other team, who won't mix back with tap, so use calmag, which isn't right at all. It's too available, and tends to add N as the second biggest nutrient, and it's a close second.

The tap isn't inherently evil, to bottle growers. Most of which need no filtration, or mild filtration. RO won't remove chlorine anyway. It's a gas. But if you do have tap things need reducing, then 100% reduction isn't the necessary target. 50% should be adequate. If you use a low pressure rated insert with about 80% rejection, you still won't see the gallons per day quoted, but can get 3x more water out, than you were.

I was crusading on this like nothing else. I needed the right filter, but factories were not getting orders. If you sell this sort of stuff, you probably had a letter from me. It took about 12 months, but eventually somebody at the top, got so much feedback, that they had to check the numbers. Today, replacement filters of the right kind, are about as easy to find as the wrong one's. Which still get supplied with new kits, as they don't know it's future use.

Most people will just buy a kit, or machine, and never even think about industry standard parts being used, and what choices that offers. 5 years back, they would sell us a pressure boosting pump for £100, rather than the right cartridge. They didn't recognise us. They just had a market for fish tanks we were exploiting. We were not saying it was for plants, and so they kept making us this high purity stuff, that needs relatively high pressure, beside the domestic supply we are using. Hence they would increase the pressure a few bar further, rather than sell a more porous filter. It was a lack of understanding. Today, I can buy fish kits, as that's what I can get cheap. Then put the filters in for plants. IIRC I'm still over 90% efficient, when I do this.
 

Dime

Well-known member
I caused a big shift in the aftermarket cartridges we can buy. The manufactures of the cartridges have always sold a vast range, but the guys making the kits, chose a medium pressure high rejection cartridge. This seems reasonable, as some people really do have average pressure, and need really pure water. It won't be any of us though. Our pressure will be low, which means a mid pressure filter, won't deliver. We don't need water cleaner than rain either. Which is another demand slowing them down. They are chasing the wrong specifications for our needs. Many people spend big, making super pure, then mix it with tap because it's too pure. Remember most bottled feeds expect help from the tap. Not pure water. Then their is the other team, who won't mix back with tap, so use calmag, which isn't right at all. It's too available, and tends to add N as the second biggest nutrient, and it's a close second.

The tap isn't inherently evil, to bottle growers. Most of which need no filtration, or mild filtration. RO won't remove chlorine anyway. It's a gas. But if you do have tap things need reducing, then 100% reduction isn't the necessary target. 50% should be adequate. If you use a low pressure rated insert with about 80% rejection, you still won't see the gallons per day quoted, but can get 3x more water out, than you were.

I was crusading on this like nothing else. I needed the right filter, but factories were not getting orders. If you sell this sort of stuff, you probably had a letter from me. It took about 12 months, but eventually somebody at the top, got so much feedback, that they had to check the numbers. Today, replacement filters of the right kind, are about as easy to find as the wrong one's. Which still get supplied with new kits, as they don't know it's future use.

Most people will just buy a kit, or machine, and never even think about industry standard parts being used, and what choices that offers. 5 years back, they would sell us a pressure boosting pump for £100, rather than the right cartridge. They didn't recognise us. They just had a market for fish tanks we were exploiting. We were not saying it was for plants, and so they kept making us this high purity stuff, that needs relatively high pressure, beside the domestic supply we are using. Hence they would increase the pressure a few bar further, rather than sell a more porous filter. It was a lack of understanding. Today, I can buy fish kits, as that's what I can get cheap. Then put the filters in for plants. IIRC I'm still over 90% efficient, when I do this.
 
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