Why do we de-chlorinate water, just to re-add chlorine to sterilize the res?

Hollatchaboy

Well-Known Member
Hey guys, I've been thinking about this and it's bothering me lol. Is it different chlorine that they add at the city water supply? Is it the concentration? Or do we not need to de-chlorinate in hydro?
 

Wastei

Well-Known Member
Hey guys, I've been thinking about this and it's bothering me lol. Is it different chlorine that they add at the city water supply? Is it the concentration? Or do we not need to de-chlorinate in hydro?
We demineralize water. There's more things than chlorine disturbing the nutrient ratio. You want to remove any minerals not available for plant to uptake. Carbonates will raise pH for example.

Short answer is, we want to know the exact ratio of nutrients available in the solution. It all depends on what's in the water if it's necessary.

EC/ppm value of the water will tell you how much total salts is in the water. Everything over 100ppm or 0.2 EC is unacceptable in hydro IMO.
 
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Hollatchaboy

Well-Known Member
Yea I get that the de-mineralization of the water is important but I'm less to believe to let water sit out for at least 24 hours to de-chlorinate. Does the chlorine change the ph/ec value of the water?
 

go go kid

Well-Known Member
no chlorine is chlorine, you are maybe thinking of chloramines in the water i think, chlorine leaves water by leaving it over night. chloramines are another kettle of fish
 

Wastei

Well-Known Member
Ok so chlorine is sodium chloride if I'm not mistaken?
Probably chloramine you if you live in the states. Evaporating chlorine is pointless, chloramine won't evaporate. The residual dosage is to low to kill of anything IME. It will react with the organics, killing of some nasties before becoming neutral.
 

Aero Grow

Member
Ok so chlorine is sodium chloride if I'm not mistaken?
Actually sodium hypochlorite and by experience plant dont like it. A good alternative is calcium hypochlorite which plants can uptake in low doses. Plus keeps the res sterile. Personally I use Pool Shock and have great results (after dialing in the correct ratios). I've killed plenty of roots in my experiments haha
 

Hollatchaboy

Well-Known Member
Actually sodium hypochlorite and by experience plant dont like it. A good alternative is calcium hypochlorite which plants can uptake in low doses. Plus keeps the res sterile. Personally I use Pool Shock and have great results (after dialing in the correct ratios). I've killed plenty of roots in my experiments haha
I've used h2o2 in the past but hydroguard works good enough for me.
 

Aero Grow

Member
I've used h2o2 in the past but hydroguard works good enough for me.
I've tried jumping on the hydroguard train so many times but never had any luck. I've seen great results tho so not knocking it by any means. Ya probably a good idea to let the water sit for 24hr if using HG since the chlorine in most tap water could potentially kill benies
 

beercan90

New Member
Probably chloramine you if you live in the states. Evaporating chlorine is pointless, chloramine won't evaporate. The residual dosage is to low to kill of anything IME. It will react with the organics, killing of some nasties before becoming neutral.
I fiddled with this for a while due to city water. Ended up buying a Small boy de-chlorinator with the upgraded KDF85 filter, later upgraded it to a full RO filter with thier kit. Gets me down to about 10ppm. I think I actually need their Chlorashield filter to fully remove chloramine, but I'm happy with what I got and sick of spending money on that lol.
 

Mirrordawn

Well-Known Member
What do you use for a maintenance dose? I tried it last run but really weak, was inconsistent because i didn’t have issues and didn’t want to mix something toxic. I might of used 200ml in a run.
Could you please elaborate on a maintenance dose?
I run about 2mls per Gallon in the system and then an extra 10% on the top off res.
 

J232

Well-Known Member
Could you please elaborate on a maintenance dose?
I run about 2mls per Gallon in the system and then an extra 10% on the top off res.
Basically just meant the minimum dose that’s effective in a system that’s not experiencing any issues, like pythium. I think I was only doing 1ml and no different on res change. I revisited this whole thing before I fired back up, I’m just going straight chiller again for now.
 

Mirrordawn

Well-Known Member
Basically just meant the minimum dose that’s effective in a system that’s not experiencing any issues, like pythium. I think I was only doing 1ml and no different on res change.
Honestly speaking. Current Culture recommends 2-5 the whole way through. But if you ran it 0.5 - 1ml, I doubt you would have any issues if everything is clean and sterile. If you see things start to build up, just bring it by 0.25 until you notice a difference.
 
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