Hello to all, I would like to communicate with you about the fog cultivation system

[WilliamWANG]

As the title suggests, I would like to discuss aeroponic systems with all the experts in this community.

I am in a rather awkward situation. In my country, region, and cultural society, showcasing and discussing this beautiful plant is prohibited. However, I have come to know and understand it. For the past decade, I've been exploring on my own, with no one to communicate or share my experiences with. It feels really frustrating. I can't even conveniently obtain seeds or nutrients like you do because although these tools are sold on online platforms, it is obvious that the police are behind these operations, conducting sting operations. I have countless stories to share about this.

Back to the main topic:

I have tried outdoor guerrilla growing and indoor soil cultivation. This year, I acquired a decommissioned plant growth chamber from a university. It can regulate temperature, maintaining a constant 21 degrees Celsius or other temperatures, and it can set the light intensity and duration with LED red, blue, and white lights that are not replaceable. The internal dimensions are only 500mm500mm1500mm. To maximize the limited space, I started exploring hydroponics for the first time. I purchased a deep water culture (DWC) system with air stones for oxygen supply. However, in the past six months, my plants have suffered severe root rot, with nearly no plants surviving.

While studying papers, I discovered that aeroponic systems can promote healthier roots, so I set one up. I replace the nutrient solution and disinfect the system every two weeks. Six weeks later, although the plants are growing slowly, they look healthy, and I am happy.

Problems have arisen:

1. I use a 10-liter bucket, maintaining a 4-5 liter water level, with a floating ultrasonic fogger for aeroponics. Now, the roots of the plants have dipped into the nutrient solution below. Recently, I've noticed a decline in plant growth rate and the roots turning yellow. I'm unsure if I should intervene. Should I soak the problematic roots in a diluted hydrogen peroxide solution for disinfection?
2. My ultrasonic fogger has been running 24/7 since the setup, keeping the growth chamber highly humid. However, I can't find a good way to stop it. I have a timer switch that operates in 15-minute intervals (15 minutes on, 15 minutes off), but I'm not sure if I should use it. Should I adjust the frequency of the ultrasonic fogger operation? For instance, running it for 15 minutes and then stopping for 15 minutes? Are there any reliable recommendations?
3. The complete loss of plants in the previous round taught me a harsh lesson, making me suspect that the root cause of the root rot might be the overly dense bubbles from the air pump and air stones, even though I soaked the air stones in hydrogen peroxide solution. But I'm still hesitant to use them. So, my hydroponic system is essentially in an oxygen-free state, yet the plants don't show signs of oxygen deficiency. Should I risk adding air stones?

I appreciate any responses from the community. Happy growing to you all!

[9fingerleafs]

Hello friend. I haven't seen anyone else growing with aeroponics around here. But several members grow using dwc. I grow outdoors with coco. From what I've heard people use commercial products like safeguard to prevent root rot. You can investigate what chemicals they use and try to get them and create your own. You can also look into commercial food production. Lots of companies growing lettuce or peppers or many other vegetables using hydroponics and there should be products for the industry. Just avoid the ones being targeted to cannabis.

[WilliamWANG]

Thank you for your response. I did find some alternatives. An interesting fact is that while I can't buy the high-end pesticides or supplements you share, similar-effect medications in my country cost only $1-2, though they are not specifically for hydroponics. I bought some medications that are said to contain Bacillus amyloliquefaciens and Bacillus megaterium, as well as some similar products imported from Japan. Next week, I will try connecting the oxygen pump. Wish me luck. I will share more information with you all if I have any updates.

[Bluey]

I grow using aeroponics and have learnt a few things mostly from online research but also my own mistakes

I grow clones and once suffiently rooted transplant them into coco. Typically they root in about two weeks but can be kept alive much longer with or without roots. I have maintained them for 8 weeks without an issue and developed roots a metre long.

What I have learnt is as follows

1. The root zone requires darkness. The roots won't grow if exposed to light
2. The pH requires adjustment at least daily, set to 5.8
3. The solution requires aeration from an airstone or similar
4. Temperature of the solution is important. 20 to 23⁰C has been working well for me
5. Relative humidity in the grow space does not seem to be so critical. My clones have happily grown in as low as 40% RH
6. An ultrasonic fogger produces a too small droplet to carry all the nutrients into the root zone. You should ideally use a mister or alternatively a sprayer. A mister requires a high pressure pump and the nozzles block easier than a sprayer on a low pressure pump. Low Pressure is simple and cheap to build and maintain.
7. The more aeration the more pH correction required.
8. The clones did not appear to be negatively impacted with the roots immersed in the solution
9. I change my solution weekly. Cleaning of the system between solution changes is not necessary.
10. The sprayer and airstones I run anywhere from 1 minute every 30 minutes to 3 minutes every 15 minutes. Both worked fine but the more often the better. Just be careful that if you run the pump more often the temperature of your solution increases.

I suspect if your plants are dying that the ultrasonic fogger may be contributing to it, but I doubt that would be the cause of root rot.