Dirbags Rockin' Rockwool Revival Thread

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Dirtbag

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Yeah if you have a res and auto watering it makes no sense to drain to waste. That’s why it’s called “waste” I guess.
It can get nasty if it's not filtered properly when getting recirculated. But the UV chamber is a really affordable way to do it. This runoff gets filtered down to 1 micron then UV blasted, and further treated with H2O2 to keep the res and lines clean.

Without some sort of effective waste water treatment, dtw works best imho. But it is wasteful.
 
MIMedGrower

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It can get nasty if it's not filtered properly when getting recirculated. But the UV chamber is a really affordable way to do it. This runoff gets filtered down to 1 micron then UV blasted, and further treated with H2O2 to keep the res and lines clean.

Without some sort of effective waste water treatment, dtw works best imho. But it is wasteful.


I thought you just need h2o2 from time to time in a res. And change the water every week or two.
 
Dirtbag

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I thought you just need h2o2 from time to time in a res. And change the water every week or two.
Perhaps, but I wouldn't feel comfortable with that level of sanitation. Large grows that recycle will use either UV or ozone for a reason. The top of my delta blocks and my runoff totes turn green with algae, and my holding tank is equally questionable. Also if one plant gets a root pathogen it could spread to all the plants. Peroxide isn't going to kill fusarium or pythium effectively imho. Plus, the UV light was only a couple hundred bucks.. its good for peace of mind.
 
Anthem

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Perhaps, but I wouldn't feel comfortable with that level of sanitation. Large grows that recycle will use either UV or ozone for a reason. The top of my delta blocks and my runoff totes turn green with algae, and my holding tank is equally questionable. Also if one plant gets a root pathogen it could spread to all the plants. Peroxide isn't going to kill fusarium or pythium effectively imho. Plus, the UV light was only a couple hundred bucks.. its good for peace of mind.
What are you using for the UV light?
Does the water run thru it?
I am just asking dirtbag because I finished a run over the weekend and one plant had some root rot and I was running UC roots at 5 percent the whole way thru. It would be nice to have an inline UV light to just kill off anything that tried to cause problems.
 
Anthem

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What are you using for the UV light?
Does the water run thru it?
I am just asking dirtbag because I finished a run over the weekend and one plant had some root rot and I was running UC roots at 5 percent the whole way thru. It would be nice to have an inline UV light to just kill off anything that tried to cause problems.
Correction 5 mils per gallon
 
Dirtbag

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This is a good article on the different ways greenhouses sanitize their runoff. Peroxide is listed but not considered as effective, particularly against bacteria, and its potentially more harmful to plants at higher levels. UV is just superior, and with a little added H2O2 also on top of that in a low dose preventative.. thats ideal in my mind.

 
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Dirtbag

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What are you using for the UV light?
Does the water run thru it?
I am just asking dirtbag because I finished a run over the weekend and one plant had some root rot and I was running UC roots at 5 percent the whole way thru. It would be nice to have an inline UV light to just kill off anything that tried to cause problems.

This is an 8gpm rainfresh system. Water goes through a 2 stage canister filter first then through the steel reaction chamber tube on the wall in the pic. From there into the res where I hit it with 45 ml of 29% H2O2 for 18 gallons of nutrient. Keeps the res absolutely spotless. Such a difference from last grow.
20210427 203508
 
j1sonbrother

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This is a good article on the different ways greenhouses sanitize their runoff. Peroxide is listed but not considered as effective, particularly against bacteria, and its potentially more harmful to plants at higher levels. UV is just superior, and with a little added H2O2 also on top of that in a low dose preventative.. thats ideal in my mind.

Although Coco is not the best choice for recycling system, will it be better if I add UV to do recycling?
But in article, it doesn't mention how much wattage UV is needed(40W?)
 
ASDFGG
Dirtbag

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Although Coco is not the best choice for recycling system, will it be better if I add UV to do recycling?
But in article, it doesn't mention how much wattage UV is needed(40W?)
In coco I'd stick to a dtw system just because of the cec, even though it isn't really that strong. Unless using real small pots.
But yes any recirculating/recycling system would benefit from UV. But it's worth doing a cost comparison, it might not be worth it if nutes are cheap and water is plentiful.

My system uses 38w lamp I believe...
 
Aqua Man

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If ya want things dead h2o2 and uvc combined... the UV Hyper activates the h2o2... extreme oxidation and the h2o2 is consumed very quickly. Not only kills things better but faster and is then inactive and ready to use.

Wanna whiten your clothes, plastic etc... yes even teeth (zoom whitening) that's how. Don't try this yourself though
 
j1sonbrother

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Technically , I think it is enough to turn on the UV for 2 hours every day in recycling system . If the UV is used continuously for more than 6 hours, the service life of the lamp will be greatly reduced.)

UV will not cause negative damage to nuts or kill some chemical ingredients ?
 
Dirtbag

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Technically , I think it is enough to turn on the UV for 2 hours every day in recycling system . If the UV is used continuously for more than 6 hours, the service life of the lamp will be greatly reduced.)

UV will not cause negative damage to nuts or kill some chemical ingredients ?
Mine stays lit 24/7. They actually say turning it off and on repeatedly shortens the life of the lamp significantly. Mine is recommended to stay on. Same with my in house UV system. The lamps are good for a year or so and are about $40 to replace

If the nutrient is left in contact with the light for too long I believe it can cause issues with iron but I don't recall why.. its not an issue just passing over the light in a reaction chamber though.
 
Dirtbag

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Well I scored 4 x 750 DE HPS ballasts and lamps for $600 Cdn off a buddy. The garden steps it up a notch next fall.

It's like a sea of golf ball sized buds in here... awesome how uniform it is.
In week 8 now, looking like they have another week or so to go. Going to start letting the ec drop over the next few days.

20210512 115220
 
420hobbygrower

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@Dirtbag What timer are you using for auto watering? Would you recommend if purchasing now, or are there any better options available now that you’re aware of? Was considering just using a smart plug that I could program from my phone, but not sure that’s the best idea.

I’m running soil, but re-doing my space to have the ability to seamlessly switch to coco/rock wool in the future, and also minimize physical labor (seriously ruined my back wahh). Already got the auto-drain set up using flood tables that drain to a condensate pump and gets pumped into my sewer line. 😎😎
 
Dirtbag

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@Dirtbag What timer are you using for auto watering? Would you recommend if purchasing now, or are there any better options available now that you’re aware of? Was considering just using a smart plug that I could program from my phone, but not sure that’s the best idea.

I’m running soil, but re-doing my space to have the ability to seamlessly switch to coco/rock wool in the future, and also minimize physical labor (seriously ruined my back wahh). Already got the auto-drain set up using flood tables that drain to a condensate pump and gets pumped into my sewer line. 😎😎
Mines named after a Greek God, Atlas or something.. has 8 on/off times and is programmable to 1 min increments.

I'd get something with one second increments if you have the budget for it. This one works ok mind you, I just dial the flow in with a ball valve.
 
Aqua Man

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Dirtbag

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Soo close...
They've been on plain water the last 3 or 4 days, runoff is below 0.2ec now. Today I shut the irrigation off to let them dryback over the next couple days, and when they're close to dry I'll kill the lights and drop temps for 48hrs. Should be finished right about week 10 of flower.

Really can't wait to take a break from growing for a few months. And super happy with how this crop turned out so far. True test will be the smoke...
20210524 090429


Wedding crasher
20210524 090558


Spiked punch
20210524 090614


Pretty clear this technique results in smaller tops and bigger mids. And im fine with that
 
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Aqua Man

Aqua Man

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Soo close...
They've been on plain water the last 3 or 4 days, runoff is below 0.2ec now. Today I shut the irrigation off to let them dryback over the next couple days, and when they're close to dry I'll kill the lights and drop temps for 48hrs. Should be finished right about week 10 of flower.

Really can't wait to take a break from growing for a few months. And super happy with how this crop turned out so far. True test will be the smoke...View attachment 1127881

Wedding crasher View attachment 1127883

Spiked punch
View attachment 1127882

Pretty clear this technique results in smaller tops and bigger mids. And im fine with that
Look fantastic... definitely would prefer bigger mids also.
 
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