Aeroponic/NFT Root Rot - Solution?

Farmer Rich

New Member
Hi All,

Any of you aeroponic growers having trouble with root rot (pythium) and what have you done to correct the problem?

My issues are largely related to reservoir temps getting a tad to warm. I've tried food grade H2O2 with little success.. I added 1 oz to 10 gallons of water, which made fairly mature plants go a bit limp. A quick reservoir swap fixed that, but now I'm a bit gun shy on how to handle this.. All my other systems have been sterilized but I have 6 in flower that I'm nursing to the end.. about 5 more weeks. In addition to the brown roots, there are plenty of healthy ones too.

Peace, Farmer Rich
 
Just the cycle for aeration.. 1 on 5 off with a reasonable drop on the return. I've had successful results in the system prior to a bout of pythium that developed in veg, got a bit better, and then worse during flower.

Current plan is 1/2 oz of 35% H2O2 to 10 gallons.. all at 780 ppm at 5.7
 
Conventional wisdom suggests adding air to your reservior.

Root rot - Wikipedia, the free encyclopedia

"Hydroponics

In hydroponic applications, root rot can occur if the water is not properly aerated. This is usually accomplished by use of an air pump, air stones, or air diffusers. Hydroponic air pumps work much the same way, if not exactly, like aquarium pumps, and are used for the same purpose. Root rot and problems with water aeration are one of the reasons that lead to the development of Aeroponics."

This is a $15 solution that could save your plants.

JC
 
A chiller is probably the best answer.. Once the res temps start getting into the 70's all bets are off on controlling fungus, especially in aeroponics. Word is Hydrogen Peroxide helps, but I haven't cracked the code in regard to strength and application.
 
A chiller is probably the best answer.. Once the res temps start getting into the 70's all bets are off on controlling fungus, especially in aeroponics. Word is Hydrogen Peroxide helps, but I haven't cracked the code in regard to strength and application.

Have you seen the thread where someone dismantled an old window a/c unit and made a chiller out of it? :smokin:
 
Sounds cool, I'll look into it but I'm not sure if I'm that ambitious, especially with winter coming. I have found a lot of good material on using H2O2 and will do a bit of experimenting as I'm needing a quick fix for one system.
 
Sounds cool, I'll look into it but I'm not sure if I'm that ambitious, especially with winter coming. I have found a lot of good material on using H2O2 and will do a bit of experimenting as I'm needing a quick fix for one system.

:allgood:
 
treat with peroxide
add ben bacteria that you killed with the peroxide
add air 24/7
add chiller
thats all I got to say bout that....
 
Hey there Farmer Rich.

You're a little low on the H2O2. I've been using 0.5ml/Liter or 2cc/USGal on start up then once a week or so throughout the grow in DWC. So for 10USG I would recommend using 20ml of 35% H2O2.

Eight years and never had root rot (knock wood), but my nute temps are around 68F all the time. My air pump runs 24/7 too.

Hope that helps.
 
Is your rez completely closed off except for the water lines? How big is it?

I ask because it might help to simply give the heat some place to go if it's completely contained. You could drill some holes at the top, use grommets and tubing to exhaust the hot air while keeping the light out. Also, it might help to move the rez to a cooler place if you have enough tubing and connectors.

Remember the higher the humidity the more heat the air will hold. And aeroponic system by nature will hold more heat. Perhaps pumping some cool air into the rootzone + exhaust will help as well.

Just some cheaper, possibly less stressful-to-the-plants idea.
 
Get your res temp down, I have been batling the same issues with my aero. Hygrozyme helps but it aint a cure all. I used bleach about .5 mil per gallon. Alot more efective than hydrogen peroxide. Change water by the next day. You can actually see it fizz and work around the roots. Does cause minor root burning but it will kill the rot along with all the good and bad bacteria and enzymes. So if you use enzymes like hygrozyme, use after the treatment to help convert dead organics in water into a useful product.
Extra air in the water won't help because only so much oxygen can desolved in water when the water temps are up.
 
toss some ice into the res that helps for a few hours of the hottest parts of the day i froze a couple water bottles with labels without glue ( ones with glue made them sick oops my bad ) and let them float around with a cap on them so it would last a little longer. the best thing i did for them tho was move them into a bigger room were it was colder ;)
 
I GOT THIS FROM A VERY SMART MAN NAMED GANJI AKA HEISENBERG AT ANOTHER FORUM IT'S LONG BUT ANYONE HAVING ROOT PROBLEMS OR NOT SHOULD READ

When a clear snot forms on roots in a DWC, and the normal course of treatment for root disease doesn't work, you probably have something called brown slime algae, which actually isn't algae at all, but a cyanobacteria. It loves oxygen and doesn't need light to grow. It doesn't care if your res is chilled or not. Safe levels of H202 slows it a bit but doesn't cure it. It can show up for DWC growers for no apparent reason even after years of successful grows. Once it shows up it's often a nightmare to get rid of. It WILL eventually spread to other DWC tubs, although it almost never gains a foothold on older well developed healthy plants/roots.

Several root conditions will cause a slimy build up; doesn't mean you have the brown slime. Common root disease is almost always caused by improper res conditions, and they improve greatly when those conditions are corrected. This isn't true of the slime. When to suspect brown slime algae is when you are doing everything right and still can't get rid of it. People who get this try the normal stuff... More bubbles in the water, cool res temps, and h202 treatments. The slime may appear to be gone at first, but comes back strong in as little as 12-36 hours. It starts out subtle like a clear coating of mucus on the roots with no odor. Plants often still appear healthy for a while, but all root production stops. In a very short time it will cover the entire root base and become thicker and sometimes turns yellow. Eventually it strangles the roots which causes pythium to set in, and at that point turns brown and finally has an odor.

The treatment is to clean up and sterilize the root base, and then populate the water with beneficial microbes. Simply running a continuous sterilizing agent such as SM-90, Zone, ect will almost certainly end with the slime as the winner. Some people have had luck running bleach or physan 20 continuously in the water, but most do not want there plants soaking in these particular chemicals. Making a microbe tea is cheap and easy, and IMO the proper way to fight this slime in a perpetual DWC garden.

Clean up the root base as well as possible. Best thing to do, if you can, is hold the plant over the sink and use the sprayer to vigorously rinse the roots, trying to get all the dead roots and gunk to slough off. It's also okay to give the dying roots a slight tug to see if they come off. Now let the roots soak in a mixture of whatever sterilizing agent you have. Physan 20 works great. This is a good time to sterilize any equipment and give the res a good scrub. After a few hours, no more than 12, of soaking in the solution rinse the roots really really well again, prepare a fresh res, and inoculate the res with beneficial microbes. Wait another 12 hours before adding nutes.

*** The smaller your roots, the less likely the are to survive a strong h202 treatment. In my experience using h202 will increase your recovery time.

Once the slime is gone be sure to practice proper res maintenance, which includes keeping any type of organic material out of the res. Trying to sterilize the res water is often a losing battle. In fact, since most hydro sterilizers fail to kill this stuff, when you sterilize the water you are removing competing microbes and opening the field to slime. There are people who use RO filters and then run their water through a UV sterilizer and still end up with the slime. The answer always seems to be beneficial microbes.

Below is my previous introduction to preparing and applying a microbe tea.


In DWC the roots sit in water constantly putting them at huge risk for disease. Some people have great luck using nothing at all. Others find sterilizing products keep their roots white, but a few of us have found that even with proper res maintenance and doing everything right, we still get a slimy build up on the roots. This is when a microbe tea can really make a difference by robbing the slime of housing, food, and actually attacking it.

By making a microbe tea with a diverse selection of organisms you will have a super tonic for you res that will ward off nasty gunk and build up while at the same time keeping your roots stimulated and growing. Best of all it can be made for just pennies per batch.

Ok so we wont be starting from scratch. You have to buy a few products. But instead of using the products directly in the res, you will be breeding them in a tea. This way, you can use a fraction of the regular dose and make your products last much longer. Plus, you will end up with a freshly active tea that is more diverse than anything you can buy on the market.

Aquashield ($12) The product composition consists of: Bacillus subtilis, Paenibacillus polymxa, Bacillus circulans, and Bacillus amyloliquefaciens. This gives you a base population of beneficial bacteria. (Aquashield can be replaced by any inoculation that contains bacillus bacteria.)

ZHO Powder ($10) The product composition consists of: Glomus intradices, Glomus aggregatum, Glomus etunicatum, Glomus mosseae, Trichoderma harzianum, and Trichoderma koningii. This gives you a base populartion of beneficial fungi. (ZHO can be replaced by any inoculation that contains myco fungi)

Ancient Forest ($14) - Soil amendment provides a high diversity of microorganisms, including more than 35,000 species of bacteria and over 5,000 species of fungi. (AF can be replaced by any earth worm casting)

EDIT* Mycogrow soluble is the cheapest and most diverse inoculant we have found. It can replace everything here except the ancient forest.


The recipe is really simple. Start with non-chlorinated water. I make 2 gallons at a time, but you can easily adjust the additives for whatever amount you wish to make. Now put the water into a bucket and throw in a couple air stones. The more air the better. You want the water to be almost turbulent from the bubbles. Now, add 15-30ml of aquashield and about 1/4-1/2 scoop of the ZHO powder. You will be breeding these into the billions so it doesn't really matter how much you start with, just don't overdo it. Now take an old sock or pantyhose and fill it with about 2 handfuls of EWC or Ancient Forest. Tie off the sock and place it in the water above an air stone, or better yet, feed an air stone down into the sock itself. If you want, you can just throw the EWC directly into the water and strain it out later with cheesecloth or even an aquarium net. Next, add about a tablespoon of molasses to wake up the microbes and give them something to eat. We will only be feeding the microbes in this tea; never add food for the microbes to the res itself. It's okay if the bennies in the res starve. You will be replacing them every few days. Now let the tea bubble at room tempeture for 48 hours. It can be used after 24, but will be more active and diverse at 48. If you use EWC you will probably notice a foam eventually, this is normal. After 48 hours you can store the tea in the fridge where it will stay fresh for about 10 days. Once it starts to go bad it will develop an odor. If you ever detect an odor from your tea, throw it out and make a new batch. Fresh tea can have a range of smells from earthy to mossy to shroomy. Bad tea smells like gym socks, fecal matter, or decay.

Initially, add about 1 cup to your res for every gallon of water, and then add 1 cup total every 3 days after. If you can, pour a little over the base of the stalk to inoculate the root crown. Your water might get a little cloudy but your roots will stay white and stimulated. When you use tea and practice proper res maintenance you can feel confident your roots will be healthy. By multiplying the microbes this way your products should last a great deal longer. Once you have eradicated slime and simply want protection from future outbreaks, adjust the tea dosage to 1 cup per 10 gallons about once per week.

If you are interested in why the tea works, or what products you may use for substitution, continue reading the rest of the thread. It is a journey I took with others to learn a great more about the tea. If you want to see how I use this tea in a cloner, jump to here.

***In an attempt to address frequent issues which bloat the thread

You can substitute just about any product you want. Any EWC will give you a good base of microbes. Any product or combo of products which contain mycos, bacillus, and trichoderma will do the trick. Don't worry about matching my exact ingredients. The exception is AN microbe products. Stay away from AN microbe products!


If you notice a dark sort of slime form after you treat with tea, stay the course. As long as you see new shoots growing you are on your way to recovery. The after-slime is harmless and will not expand or stall roots. New root tips are what you want to see.

Do not use tea with h202, sm-90, Zone or any type of sterilizing product. Do not filter tea beyond 400 microns.

If you have slime attacking plants with very small roots, adding housing to your res like a lava rock or koi pond mat will make a big difference. Place the housing in your tea brew for the duration and then move it to your res.

No one has reported sprayers clogging from using regular tea. But, if you are concerned you can also try aquashield by itself without brewing. High pressure nozzles will kill most microbes, medium pressure and simple sprayers are fine.


Take care of impropoer res conditions FIRST. Even the tea will not save you from disease if you do not have enough oxygen or proper temperatures. Res water should be around 75f with bennies. Air pump should be at least 1wt per gallon. Light proof your buckets!



THIS IS WHAT ALL OF YOU NEED TO READ IT WILL TAKE CARE OF YOUR ROOT PROBLEMS AND YOU WILL LOVE IT I SURE DID!!!!
 
Where is your Resevoir? Is it in your actual grow room?
I also had this issue, I pretty well lost my grow to it because i ended up getting too much algae - it was in the lines, in the pump, - everywhere basically.

Another issue i had that i think contributed to the heat was that in the root chamber i would leave a 1/2" of standing water, will be fixing this by putting drains on the bottom instead of the bottom of the side.

There was no way i could keep it cool - I was putting 2 litres of ice in it every 4 hours for a couple days until i gave up on it. pH was going nuts because algae would reform in a matter of about 2 days. Im wondering if anybody else can think of some sort of another small chiller? I dont even need a 1/10 hp chiller im sure. Ive heard of people pulling apart the water coolers and adapting them, i hear you can get them off craigslist for like 50$. might be an idea.
 
Hi: I had the same problem got brown slime during veg using bubble buckets used H202 @ 29% 1ml/gal and increased air 2 weeks all gone but it took about 3 weeks for the plants to recover fully. I transferred from bubble buckets too my 1st RDWC system and again I had trouble and again it turned out to be too little air. Found some very good info on this site about it this pertains mostly to DWC but I used aeroponics before this grow and this information is good for both. https://www.-------.com/cannabis-fo...RDWC-info-on-pumps-and-air-pumps-for-everyone!
 
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