How to operate a sterile hydroponic system
- Thread starter jijiandfarmgang
- Start date
Budley Doright
Well-Known Member
rkymtnman
Well-Known Member
only if you're running aquaponics, your fish wont' like it.
chloramine is probably an even better disinfectant than chlorine since it doesn't break down when exposed to oxygen
redi jedi
Well-Known Member
Why? Chloramine works too. I dose my tap water with shock before I add nutes, not an issue IMO.
Rahz
Well-Known Member
Hypochlorous acid disassociates into hypochlorite. This indicates there's no hypochlorous acid in pool shock or bleach. Presumably since hypochlorous acid doesn't readily react with nitrogen it will stay in solution longer, but how long I'm not sure and as soon as it disassociates into hypochlorite in a nutrient solution it will convert into chloramine. Once an effective level of hypochlorous acid has dissasociated the protection is about zero. UC Roots, which is HClO based doesn't specify how long it provides protection, so it's possible it remains mostly intact with proper PH for a week or more, but that's just a guess based on a product label.
The dosage recommendation for Pythoff (chloramine based) at the labels listed gauranteed analysis comes out to 29 ppm. Conventional wisdom suggests 4 ppm hypochlorite keeps water sterile, which suggests chloramine is 7x weaker than hypochlorite.
The main point is that if you add bleach to a nitrogen solution, there's not going to be any hypochlorite in the solution. It get's converted into chloramine within minutes. Chloramine sterilizes just fine, but if you're dosing based on 4 ppm hypochlorite you end up with around 4 ppm chloramine which probably isn't going to offer any protection. That is also a guess based on product lables, but I think it's worth looking into.
The dosage recommendation for Pythoff (chloramine based) at the labels listed gauranteed analysis comes out to 29 ppm. Conventional wisdom suggests 4 ppm hypochlorite keeps water sterile, which suggests chloramine is 7x weaker than hypochlorite.
The main point is that if you add bleach to a nitrogen solution, there's not going to be any hypochlorite in the solution. It get's converted into chloramine within minutes. Chloramine sterilizes just fine, but if you're dosing based on 4 ppm hypochlorite you end up with around 4 ppm chloramine which probably isn't going to offer any protection. That is also a guess based on product lables, but I think it's worth looking into.
rkymtnman
Well-Known Member
doesn't the ratio of chlorine to ammonia have to be close to 5:1 to produce chloramine?
if you are adding 1ppm chlorine to a res with maybe 9 ppm of ammonia (7grams maxibloom), your ratio is not correct to even produce chloramine?
Rahz
Well-Known Member
That's just the ratio needed to produce chloramine without chemicals being left over, possibly uses ammonia because it's the cheaper form of nitrogen. I'm not a chemist so I can't give you hard answers, but like I said it's something worth looking into.
This all started for me when I noticed 20 ppm hypochlorite in a nutrient solution wouldn't phase the rot, however 5 ppm in plain water would turn dark brown rot light tan within several hours. It seemed like the nutrient solution was affecting the ability of the bleach to sterilize so I started doing some research.
I would be happy for an authority on the subject to drop in and clear things up.
rkymtnman
Well-Known Member
i'm with ya. my last chem class was in 1987.
all i know in laymens' terms is that pool shock works well.
i'm using a hydroguard replacement at the moment for the last few grows. works just as well too.
Thanks
That's assuming the concentration of what ever you're adding is 100%, right?
If you were adding household bleach, it's usually anywhere from 4% to 10% hypochlorite, so 0.001ml per L or 0.00379 per gallon wouldn't get you anywhere near 1ppm. It's that right? I almost had a heart attack before I realised that as I use 2.5ml bleach (4%) every 3-4 days for both of my my 32L res
redi jedi
Well-Known Member
1mg/L = 1ppm, but that calc is for adding dry concentrate to water, not sure if it works for liquid bleach. Go back to the first page, all the math is there.
fartoblue
Well-Known Member
Some great points made here Rahz on an old thread.
This may be the reason the CH shows on my dip strips at 3ppm but as soon as nutes are added it don't show at all as chloramine dosn't show on the strips.
Maybe it would be a good idea to flush the plants with plain water HC solution before adding the nutrients.
redi jedi
Well-Known Member
Gotta remember rahz had rot before he started dosing with chlorine which is not how to use chlorine. Its best used as preventative measures. So even if its converted to chloramine, its still disinfecting. Add your shock first, then add nutes and your good to go...
fartoblue
Well-Known Member
Thank mate, my only worry is when to re-dose if I can't measure it with strips. Say I let my res go 14 days between changes.
rkymtnman
Well-Known Member
if you went 1ppm every 3 days, you'd be fine. at max you'd be 5ppm at day 15 or so.
rkymtnman
Well-Known Member
when i noticed a bit of rot, i'd run just the poolshock and water for a few hrs. then add nutes.