I know everyone has been talking about “shock” but what about regular bleach? How much bleach should I use, per gallon, to prevent algae and root rot?
Also, should I cover up/paint my orange HD buckets?
2 Likes
I had completely forgotten about this. I had a similar, but less severe issue early in my first hydro grow. My rez was located under my grow table in an awkward place to get to or to see into. I installed a light above the rez under the table so I could see what was going on. Several times, I would forget to turn the light OFF. Sometimes, but not always, I would get some similar looking sludge building up on the rim of the rez and the air line tubing, but then it would go away. Looking back on it, it was worse directly under the light. Now Im thinking it was the light causing it to form when I forgot to turn it off.
Mega Crop has enzymes in it already, so Im assuming those enzymes, and/or the Hydro Guard I started using at the time that made it go away.
2 Likes
Shine a torche onto the side and if you can see light then yep tape them up 
Edit - people do use bleach but I’ve never attempted it myself. I got enough pool shock to last me 500 grows for less than £10
2 Likes
I dont use a sterile rez, but I have read a lot about it. There are some scientific studies I have read that say sterile rez technique is a bad idea. By the time you add enough bleach to the rez to actually kill any pathogens, the concentration will be high enough to damage the roots.
On the other hand, there are a shit ton of people who swear by it 
This is not an unusual situation in growing weed 
There are two downsides to using regular bleach . For one, its a lot cheaper to use pool shock. It is far more concentrated and a lot cheaper. A $5 bag of powdered pool shock will make hundreds of gallons of concentrate that can treat 1000’s of gallons of rez water.
The other thing is that most liquid bleach breaks down fairly quickly and gets less potent once the bottle is opened. So you will not be able to maintain a consistent dosing.
You can calculate the dosage you want in PPM with some math.
1 MG (.001 grams or 1 milligram) of chlorine added to 1 liter (1000 grams) of water = 1 PPM = one part bleach to one million parts water = 1/1,000,000 million.
So if we take @HappyHemper example above, he used .5 gm of pool shock in 66 liters of water.
The pool shock I bought at WalMart has an “Available Chlorine” concentration of 48.6%. That means he added .5gm x 48.6% = .5 x .486 = .243 gm of chlorine to 66 liters of water.
Thats 243 mg of chlorine to 66 liters of water = 3.68 PPM.
The short version of the formula is total mg of chlorine / liters of water = PPM.
My bottled bleach is - very roughly - 10 times less concentrated. Keep in mind, not all pool shock or bottled bleach has the same concentrations, so you need to read the label.
6 Likes
what he 
said 
20 character limit sucks ass.
2 Likes
I been saying that since the first day I used OG!!!
3 Likes
According to my recent experience, hell yeah.
What you see here, wrapped in aluminium tape, are white PVC bulkhead fittings. They were a low-flow epicentre of algae growth. The PVC allowed enough light for it to thrive.
This is while I was dosing with h202 at every res change, and every 4 days inbetween.
My conclusion? H202 doesn’t do much. Pool shock is where it’s at. And no light.
PS that yellow hose is black inside, and the buckets are black. Reflectix is more for insulation
2 Likes
The slime is back on the roots… and pH went up 0.2 points overnight, much quicker.
It has been 4 days since my last application of shock, so I guess that is how long it lasts.
The slime is, however, white now. Maybe it is simply the dead stuff clinging onto root balls? I hope it is. But then why would pH jump so fast? Felt inside the buckets, airlines, and recirc lines all clear, no slime, so just roots? That ain’t good, because some root hairs are clearly unhappy from being suffocated by slime. Roots have very little branching and are looking haggered.
Re-dosed with shock to a calculated 3ppm over the system capacity
Don’t have time to take a picture and upload, gotta run to work
The growth of the plants has slowed; ne deficiencies, but no new roots either, and if anything a little too much N. I think upon my return from work i will drain, refill to a max of EC 1.0 including calmag to try and tease the roots out, and try to mechanically clean the existing roots a little better.
2 Likes
Unusual that it’s came back but now its white. Are you 100% sure no light can get into the pots/buckets? I want to keep saying is a light leak of some kind.
What worked for me hasn’t helped you so I’m at a loss.
2 Likes
I’ll keep digging I’m sure i’ll figure this out eventually. Plants have not started dying yet, so worst case = longer veg. I got time to get this right, which is why the other tent is full of autos.
Just sucks that i have to be working instead of tinkering in the basement 
2 Likes
If in doubt black it out (black duct tape) I used two 50m rolls on 4 buckets just to be 100% sure
2 Likes
Got the rez flushed and re-loaded with 3ppm calcium pool shock and about ec1.0 combined calmag and 1+2, plus a half-doze vitamins b.
Removed most of the roots. The hairs on the longer roots went brown and slimy, I wiped off what I could and pinched the knots and longer nasty roots right off.
I’ll just pretend I’m back a week that’s all 
What I am looking for with this lighter feed is hopefully the plants putting more energy into the roots. Tops are healthy, I hope they pick up.
Edit: some root pics if what they are like now
Do you think that’s good enough or should I prune them more? Some of them are still kinda stuck together
And another one
I see in post 14 what looks like an airstone.
Another poster, around a year ago (can’t find the post), posted a similar problem (in the form of a contest), but his pH was changing much more rapidly then yours. He determined his “cheap airstone” was shedding minerals into his water. You say your pH is holding steady for a week. Maybe yours is a better quality stone than his and only shedding minerals at a very small rate. Did any of the pH rises occur after you were doing something with your nutes? Or adjusting something? Is it old? Is it plugged?
I know this has little to do with your slime problem and maybe the slime is responsible. If the pH creep continues after the slime has gone away, it might be worth purchasing a new, high quality airstone. There is a different type of aeration device for aquariums as well, it is a foam tubing and has no minerals to leech.
6 Likes
Thanks @Cobra50, this is something to look into for sure. The airstones were soaked/working for a good month in sterile water while the rest of the grow was set up and clones rooted, but that doesn’t mean they are done leaching.
They are large soda-pop-sized stones from a reputable store, not ebay, this is my first grow on them, and they seem to be performing really well. But i will look into that foam tubing aeration too.
Oh, my poor snipped roots. Plants are not showing any issues though, except for early magnesium deficiency, which is expected with root zone problems. Will be doing foliar to help
3 Likes
So, you switched away from the Mega Crop, and the slime still came back? If so, I guess that rules out the nutes as the problem.
Your roots not liking the chlorine is why I have resisted doing a sterile rez for so long.
Maybe try a lower PPM level, but refresh it more often? Most of the recommendations I have read are for 2ppm every three to four days.
I went with 4ppm to kill of the crap in my rez, but I plan to only do 2ppm ‘maintenance’ doses from hear on.
Some of the university studies I have read say you need much higher doses - like 100-200 ppm - to actually kill the crap, so maybe you didnt kill it all with that first dose. Of course, hi doses will do more damage to the roots…
1 Like
I’m not sure it’s the chlorine @anon32470837, too many confounding variables. Slime came back a different color, so it is possible that it was simply the dead shit that got dislodged from all the tight places and got filtered by the roots through enough turbulence. Then suffocated the roots, which made the little hairs die.
That, so far, is my best theory, because the slime was white… it’s the stuff hidden within it that was not, and that was dead root hairs. We’ll see what happens. All those assholes on YouTube make this DWC thing look way too easy
1 Like
If thats the case, then adding that filter in the system might do the trick.
hahahaha! Yup. Pot heads always seem to think things are easy. They are if your too stoned to pay attention
2 Likes
A copy and paste from here
https://extension.umd.edu/hgic/topics/chlorine-toxicity
Excess Chlorine
Scorched leaves may be the result of chlorine toxicity. Chlorine is a micronutrient, essential to plant growth. However, too much chlorine can accumulate in leaf tissue, resulting in leaves with a scorched or burned appearance. Trees with scorched leaves have brown or dead tissue on the tips, margins, or between the veins of the leaf. Leaf tissue may appear bleached, instead of scorched. Leaves may be smaller than usual. They may yellow and drop early. Chlorine toxicity can result from air pollution, in the form of chlorine gas, or from excess chloride in the soil.
Excess chloride can build up in the soil from swimming pool runoff, irrigation water, or excess soil salts (sodium chloride). Chlorine (Cl) converts to chloride (Cl-) in the soil and is absorbed by plants in this form. Chloride toxicity is most common in irrigated, dry regions, seacoast areas, and near roads frequently treated with salt in the wintertime. Chloride levels can be reduced with the use of gypsum. Incorporate gypsum into the soil at a rate of 58 lbs. per 1000 square feet, in loam soils. Less gypsum is needed in sandy soils, more in heavy clay soils. Water thoroughly to leach toxic levels of chlorine from the soil.
Damage to plants from chlorine gas is less common than damage from other air pollutants, such as sulfur dioxide, fluoride, and ozone. Chlorine gas is a by-product in the manufacture or incineration of glass, plastics, paints, and stains. It is released from refineries or as a result of chemical spills. Reducing air pollution at its source is the best solution to reduce damage to plants and people. Careful watering practices can reduce air pollution damage to plants. Soil should be dry during periods of exposure to air pollutants, followed by thorough watering after exposure. Wetting the leaves of sensitive plants may help to reduce damage during periods of poor air quality. Trees sensitive to chlorine are ash, boxelder, Siberian crabapple, dogwood, horse-chestnut, silver maple, sugar maple, pin oak, sweet gum, and yellow-wood.
3 Likes
Excited to say, the plants are showing signs of recovery, with a vengeance.
I’d love to say they didnt skip a beat, but they did. Growth slowed to a crawl, but nothing yellowed, nothing died.
Here are the beginnings of what looks like a fuck of a rootball:
6 Likes
So what would you say has been causing the problem?? Light leak?? Ph swings?? A combination of both??
3 Likes