Cloning using UV light in reservoir

I am using a DIY aeroponic clone machine. Not having much luck. getting slimed. Once I get slime it is all over. No roots just slime where roots should be.

I want to use a UV light to prevent the slime from developing in the bucket. I have a 10 W UV LED light that I have inserted into the water reservoir. What if any effect will UV light have on the development of roots?

Good idea or stupid idea?

I would have to suspect the UV will be just as damaging to the root tissue as it would be to the slime, and will not help at all.

The biggest things that would help – would be making sure you have enough aeration, and I mean a ton of aeration, maybe keeping water temps to around 69F, not much lower as it will slow root growth and much higher than about 72F and you lose too much dissolved oxygen in the water (the water just can’t hold dissolved oxygen very well at higher temps) which will promote the growth of the bad slime (anaerobic bacteria), and also using a pro-biotic to help counter the bad microbes that seem to be attacking the clone stems.

Maybe sterilize everything with hydrogen peroxide, maybe add a more powerful air pump and larger or more air stones, and introduce good microbes with something like “Great White” or “Hydroguard”.

Happy growing,


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MacG…I had the same problem and I’ll bet the farm he didn’t disinfect his cloner " AS I DID " I removed all clones and placed them all in gal buckets and took the cloner in and scrubed it down good with disinfectent air dry and the washed it with hydrogen peroxide and 90% alcohol than refilled with rain water PH at 5.5
Took a clean razor dipped in the alcohol and scraped and wipped all the scum off made a clean 45 degree cut dipped in hydrogen peroxide and placed back in the cloner.
That was 3 days ago and all is well


Another thought, you say you are using a DIY aeroponic cloner and not a “bubble”/DWC cloner.

If you are using a submersible pump to spray the clone stems, this may be doing more harm than good if the submersible water pump is adding the majority of the heat to the system’s water.

You might want to re-think the idea and maybe make it a bubble/DWC cloner instead of a aeroponics cloner, replacing the water pump with air pump and air stone – this could reduce the temps enough and increase dissolved oxygen enough to get successful results. You would just raise the water level to just barely having the stems submerged, or close enough to the bottom of the stems that the bubbles at the surface will splash water onto the clone stems.

This is the type of system I use for cloning with a nearly 100% success rate and water temps maintained low enough by only being inside the house at normal house room temperatures.

Also be sure that the root area is light proofed.



You growers are great. gave me a lot of new ideas. Appreciate your taking the time to help me. Thank you

one different thing i do , for cloning in dwc is no nutes lots an lots small aeration bubbles and add 1/4-1/2 tsp clone nex rooting powder per gal of distilled water change solution every 3-4 days once you get roots 3-4 inches long move to dwc grow zone and add nutes. usually in 1 1/2weeks they will be major roots . and the rooting powder helps prevent slime “i believe” . lots of bubbles to … lots of small soft bubbling bubbles to big of bubbles can tare small baby roots off.

Yup the pump is sbumersible and I did notice that the water was …well warm to say the least:
Im going to take that pump out and replace it with an exterior air pump. The water is getting to warm and creating more problems.
And yes there is no light at all to eighter roots or the plant
Thank MacG I think your input will do the trick. I’ll keep you posted on the change


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How goes the battle? I was in the same boat. Tried water chiller to control temps, UV disinfection, Ozone treatment, as well as Calcium Chloride shocks and also Plant Success Soluble “Orca” as well as trying the almighty Botanicare Hydroguard. Still in the end cloning is taking to long as plants become sicker and eventually the slime will find a way to overcome everything. It’s vicious, malicious and extremely aggressive slime that even attached itself to the UV light used in one of my experiments.

You may not like it but I’m going to tell you the best way to deal with it and the only REAL solution I could come up with after many frustrating attempts and tons of science and trial and error scenarios. -->Stop using that water<-- (very hard to do, I know…)!

Find an alternate source of water, at least for your cloner machine. That means fill up at a friends in the city and yes properly treated city water with lots of chlorine works great in fact it’s amazing. After dealing with slime ridden well water it will blow your mind. The second option: Buy some water in a bottle or bottles. Specifically water marked that it was “obtained from a municipal water source” works good but anything is fine just don’t bother with distilled get municipally sourced or spring water.

The municipally sourced water is water that gets bottled from and in a city where the water that gets sent to the taps is considered good enough to be bottled and sold. Although what gets bottled and sold may not be monitored too well, that’s another story and is neither here nor there when it comes to the issue at hand. The great thing about this water goes back to my original statement that treated city water is the best water to use.

Also not knocking some of the other great suggestions out there or the guys giving them but in my many experiments with this issue I have noticed that adding air bubbles to the water only exacerbates the issue causing even more slime to grow yet even faster. Also any attempt to filter the slime will also end up creating essentially what can be more slime. The slime loves to attach to pump inlets and other plastic surfaces as one will notice. If you can catch the return water in a system in a filter sock that is suspended in the air it can aid, somewhat in the control of the slime but this is still not ideal, however, if suspended in the air after the return water pipe it can catch some of the slime and cause it to dry out in the filter sock.

Some very basic but helpful info on slimes

I hope this helps the masses.