Does recirculating DWC through a UV light still need a chiller?

Cl@rksville

Well-Known Member
Not often I ask for help but needs must... If I run a RDWC through a UV pond filter it kill the bacteria responsible for root rot, yes? So I have a chiller option and please understand I have done loads of single pot DWC grows but never this RDWC with twin tanks, ones a res and the others a header pot. So if theres plenty oxygen and no bacteria does the higher nutrient temps still cause poor root growth?
 
As long as the pond filter totally sterilises the water then no but it's worth noting that nearly every base nutrient in the game bar a few contain ammonium nitrate which needs a nitrogen fixating bacteria to break it down. In a sterile system this will cause a large portion of nitrogen to be unavailable to the plant.

I'm waiting on an ozone generator getting delivered which I will use to sterilise (ditching the h2o2). Gotta save some long term money not buying oxidising agents.

Check these out .... Crop nutrients shiva

It's one of the only sterile nutrients out there, I just took the plunge on the 20l.

As long as you can keep it oxygenated then about 24-26c will allow for more nutrient availability and imo can only lead to nice healthy roots
 
Last edited:
https://letsgrowild.wordpress.com/2...read-for-any-water-culture-growers-out-there/

"If you RO your water, sterilize it with either Hydrogen Peroxide, UV Filter or Ozone and use a high quality “chem salt” style of nutrient that has quality ph buffers added, you system with run well; and if you run something like SM-90 or SNS or even Azamax then Gnats & other nasties are a non issue. I hope this article clears up a few questions about DWC & helps you find out for yourself how easy this form of Hydroponics can be. Just remember this is not dirt, so quit trying to mimic dirt & realize the full benefits of this style of growing. So keep it clean, keep it sterile & watch in amazement."
 
Not saying that is the final word but when I run DWC I run full synthetics. If you have a job or are away I think my UV filter and the synths make it far easier to keep control of the res. Just my opinion here.
 
https://letsgrowild.wordpress.com/2...read-for-any-water-culture-growers-out-there/

"If you RO your water, sterilize it with either Hydrogen Peroxide, UV Filter or Ozone and use a high quality “chem salt” style of nutrient that has quality ph buffers added, you system with run well; and if you run something like SM-90 or SNS or even Azamax then Gnats & other nasties are a non issue. I hope this article clears up a few questions about DWC & helps you find out for yourself how easy this form of Hydroponics can be. Just remember this is not dirt, so quit trying to mimic dirt & realize the full benefits of this style of growing. So keep it clean, keep it sterile & watch in amazement."
No I use plain tap water with no issues, what I should ask is forget root rot its gone its not an issue lets pretend the UV system works for a moment... I want to know quite simply can the plant take on nutrients at higher water temperatures when the nutrient is highly oxygenated, as in 25 degrees c?
 
65-75 F is the ideal range so your 25C will be just fine. If it hits 80F/26C then start thinking of cooling methods.
 
I wouldn't be using h2o2 with such high oxygenated water either, its seems redundant.
65-75 F is the ideal range so your 25C will be just fine. If it hits 80F/26C then start thinking of cooling methods.
So lets say it hits 28 which under normal circumstances creates bacterial heaven, but we have none because its dead then we are on the right channel, what would happen if the dissolved o2 content was massive like 95% or so, will my roots behave in the same way as they would when its cooled to 20c where I like it to be with the cooler? Bear in mind the o2 is constantly getting artificially supplied 24/7... Basically do roots feed regardless of temps as long as they remain in good health with high o2 content?
 
W
I wouldn't be using h2o2 with such high oxygenated water either, its seems redundant.

So lets say it hits 28 which under normal circumstances creates bacterial heaven, but we have none because its dead then we are on the right channel, what would happen if the dissolved o2 content was massive like 95% or so, will my roots behave in the same way as they would when its cooled to 20c where I like it to be with the cooler? Bear in mind the o2 is constantly getting artificially supplied 24/7... Basically do roots feed regardless of temps as long as they remain in good health with high o2 content?
If the res temp rises simply blast more O2 into the water. Also watch the EC/PPM as the temp rises. Hope this link helps.

http://www.simplyhydro.com/nutrient_temp.htm

In my experience as long as the res temp stays stable even if it is slightly high you can adjust your EC while blowing as much air into the soup as possible. Meaning big motherhumping pump.
 
I'm a voice of dissent here. I've been aerating my RDWC system without airstones for years and it's highly effective and reliable.

I run the RDWC water itself over the hydroton stones in each plant's netpot. It runs down the stones, down the roots and back into the water beneath, oxygenating itself as it goes. Plants love this approach.

I found that no amount of sterilisation would solve my root root problems before I brought my water temperatures under control, meaning below 70F/21C. After I began chilling my RDWC system, no amount of sterilisation has been necessary. I've tested this; I've deliberately allowed buckets of dead roots to decay and then tossed the water directly into my control bucket. Exactly nothing untoward happened.

Because of this personal experience, my advice is to find ways to maintain your RDWC water temperature at or below 20C as opposed to trusting some magic sauce.

Part of the reasoning is that water can hold more dissolved oxygen at lower temperatures than it can at higher ones. Most of the nasty root rot bugs prefer an anaerobic environment. Keeping your water cool is the best way to create an environment that simply isn't supportive of their life cycle.
 
I would imagine of he has a chiller option after he reads the post I linked he will decide whether he wants to use it or not. If I had a chiller I would have used it. I have used waterfalls and tubing with holes I made. Airstones clog to easily and too quickly.
 
I would imagine of he has a chiller option after he reads the post I linked he will decide whether he wants to use it or not. If I had a chiller I would have used it. I have used waterfalls and tubing with holes I made. Airstones clog to easily and too quickly.

Since I haven't tried it, I can't recommend it personally, but I've seen topfeed RDWC where the water is pumped up and runs down through the rocks like mine and it wasn't chilled. The water level was kept lower so turnover was faster. Maybe the filtration effect of running over the rocks helped keep the bugs down, no idea if that's true. Worth a look, perhaps?
 
Since I haven't tried it, I can't recommend it personally, but I've seen topfeed RDWC where the water is pumped up and runs down through the rocks like mine and it wasn't chilled. The water level was kept lower so turnover was faster. Maybe the filtration effect of running over the rocks helped keep the bugs down, no idea if that's true. Worth a look, perhaps?
I had no chiller so had no choice bot to work with it. I had to gradually raise the PPM higher than if I had had a chiller.Obviously we are tempting lockout. But what can a guy do if he has no dough for a chiller and in Alaska trying to get one was ridiculous. Chiller $150 + $75 S/H. Ask Sunni!
 
I had no chiller so had no choice bot to work with it. I had to gradually raise the PPM higher than if I had had a chiller.Obviously we are tempting lockout. But what can a guy do if he has no dough for a chiller and in Alaska trying to get one was ridiculous. Chiller $150 + $75 S/H. Ask Sunni!

So here I'm thinking, WTF do you need a chiller for in Alaska?! Just run the line outside?
 
I wouldn't be using h2o2 with such high oxygenated water either, its seems redundant.

So lets say it hits 28 which under normal circumstances creates bacterial heaven, but we have none because its dead then we are on the right channel, what would happen if the dissolved o2 content was massive like 95% or so, will my roots behave in the same way as they would when its cooled to 20c where I like it to be with the cooler? Bear in mind the o2 is constantly getting artificially supplied 24/7... Basically do roots feed regardless of temps as long as they remain in good health with high o2 content?

In theory, if there is ZERO chance of bacteria then they should be fine, just ask a freshly rooted clone on a heatmat. I asked my buddy who does ozone treatment on a under current system. He said even with proper sterilisation he wouldn't trust his res at 28c.
Maybe at higher temperatures even though the solution is highly aerated the water may be unable to dissolve the oxygen.

Oxygenation is different to oxidisation when it comes to killing nastys. When you use hydrogen peroxide or ozone you're diliberately adding millions of unstable oxygen atoms which break off from their O2 and h2o and go looking for organics. When they come in contact the extra unstable atom attaches itself and the oxidises itself killing anything live in the process. While adding more air is never a bad thing imo, your only adding O2 which is stable so wont do the same as an oxidising agent.

Oxygenation can make it hard for anaerobic bacteria to get a hold but can't oxidise them like o3 or h2o2
 
I'm a voice of dissent here. I've been aerating my RDWC system without airstones for years and it's highly effective and reliable.
Not dissent at all tty, in fact its a good method and they seem to like it ime. I have a chiller and its fine running the nutrient through it and I can control temps down to 7dc. My question is can the roots perform their task of supplying nutrients from the reservoir to the shoots more efficiently if the nutrient is heated in an artificially oxygenated bacteria free environment? Does the oxygen dissolve in the water but quickly vanish in the roots base before it has a chance to perform its task? I was sort of hoping for a miracle answer of "Get on the higher temp nutrient technique like ASAP lol!
 
So here I'm thinking, WTF do you need a chiller for in Alaska?! Just run the line outside?
Not when it hits -28F. And when the high is less that +32 in winter? If a guy is home and can watch it that's one thing. But several magnetic ballasts and growlights in a well insulated room it gets quite warm. If you are at work only an idiot there leaves a window even cracked in warm weather or after hibernation is ending. Do it and come home to a grizzly in your house or find it trashed by one. Black bears chewing anything including fluid lines after hibernation trying to eat anything. You obviously don't live near these critters?
 
Not when it hits -28F. And when the high is less that +32 in winter? If a guy is home and can watch it that's one thing. But several magnetic ballasts and growlights in a well insulated room it gets quite warm. If you are at work only an idiot there leaves a window even cracked in warm weather or after hibernation is ending. Do it and come home to a grizzly in your house or find it trashed by one. Black bears chewing anything including fluid lines after hibernation trying to eat anything. You obviously don't live near these critters?

My thought was to use a water line that merely went outside, looped a few times to shed heat and then went back inside. No open windows, no smell to attract bears.

No, I do not live in Alaska. I live in a mid sized city in Colorado, and the closest I've ever been to a bear was when my buddy hit one with his Jetta coming down the canyon one evening. It was a glancing blow, and we drove back to see if we'd killed it. Nothing anywhere on or next to the road, so we figured he was okay!
 
Not dissent at all tty, in fact its a good method and they seem to like it ime. I have a chiller and its fine running the nutrient through it and I can control temps down to 7dc. My question is can the roots perform their task of supplying nutrients from the reservoir to the shoots more efficiently if the nutrient is heated in an artificially oxygenated bacteria free environment? Does the oxygen dissolve in the water but quickly vanish in the roots base before it has a chance to perform its task? I was sort of hoping for a miracle answer of "Get on the higher temp nutrient technique like ASAP lol!

That whole lecture above about water being able to hold more dissolved oxygen at lower temperatures than higher ones was meant to explain why high temps won't work in deep water culture. You don't like the rules, take it up with Mother Nature. I'm an engineer; I don't make the rules, I just bend them to my will...
 
Back
Top