Why Aren't Undercurrents More Popular?

[timmur]

Here's a link to my thread. Latest pic of my grow. If you look back you can see the room before plants went in.

 

[UCMENOW]

Making a case for DWC over RDWC is like arguing the virtues of hand watering vs a drip system. For those who must, hand watering is a vialble option and works well. When its time to move from gardening to farming there becomes a higher need for consistency, automation and redundancy. Once this paradigm shift takes place the way to best operate becomes more apperent.

 

[RoeBuck]

Commercial?

You'll find significant savings on labor (one of your highest costs) by going straight dwc. The 'sterilization' times are reduced to a quick scrub and rinse of the res. Infrastructure costs will be significantly less with DWC, simple tubs vs. what rdwc requires. Running airpumps, instead of large water pumps, is a large savings on electricity and start up costs.

DWC is truly the lazy man's hydro for smashing results. :)

Have you read "Ask lucas" before? The reason I ask is because you mentioned using an add-back reservoir for 'stable pH.' In my experience, a full and cyclic pH swing grows vastly cleaner and higher quality cannabis. The old overgrow FAQ (and a lot of misinformed people) talk about using an add-back reservoir for pH stability, when in reality you want a full and healthy swing to be present. I remember a quote from Lucas where he strongly advises to use only plain R/O water for add-backs and is wondering where the "pH stable" junk came from.

Keep up the good work!

Douglas

lol, I guess I'm already a commercial grower, just not a legal one.

While I agree that cleaning up a bunch of DWC buckets may be less time consuming, I don't find cleaning these RDWC systems to be a burden. I drain, fill with tap water, add a couple cups of bleach and let it run for 24 hours. Scrub, drain, refill with tap water, circulate a few hours, then drain. Ready for the next grow.

The cost of running a water pump is pretty insignificant. A 500 gph mag drive pulling 50 amps costs less than $4 a month at my 11 cent per kilowatt rate. I didn't run the numbers on air pumps but I doubt they would even cost that much. I suspect both add up to less than 2% of my monthly electrical costs. Granted, overall startup costs can be high, mine are around $15k, but that was fully recovered on the second 8 plant grow. (I started with 1 system and added the second after my 3rd grow.) Having run these systems for a couple years now I wouldn't purchase another turn key system, but would build it myself. That's what I did for my veg room. A two tote, 8 plant RDWC system that cost less than $500 to build.

The biggest issue I see with running a series of DWC totes is water chilling. I run a 1/10 hp chiller on each system. Trying to cool 16 individual totes would be hard to manage. How are dealing with this?

I still have pH swings but they aren't as severe or as dramatic. I generally run my top off at about half strength of my system. I start my pH at around 5.6 and it slowly rises to around 6.0 over about 10 days. I then readjust. By the time it goes through 2 cycles it's time for a system change. I did try running straight RO but found the pH rose too quickly and the nutrients were depleted a lot faster. This might be preferable in DWC where system changes are routinely done weekly, but adding feed to the top off seems to work better when the system is only being changed ever 3 weeks.

 

[RoeBuck]

How many total plant sites would you be comfortable running without hiring a crew? (assuming you'll contract out the trimming or else helpers with machines) And how many per room do you think is the sweet spot for practicality?



Show us? I'd like to see one of these larger RDWC operations, sounds intriguing.

That's something I haven't given a lot of thought to. Right now it's my partner and myself. I take care of the day to day and he helps out with cleanup, setup and trimming. Of course, trimming is the most labor intensive. We can usually trim 8 plants in about 5 days, working 4-5 hours a day. Neither of us are youngsters and that's about all our backs can take. That's the primary reason we went with two 8 plants systems instead of one 16 plant. We stagger the grows so we're only harvesting one system at a time. So we're harvesting about every 5 weeks, depending on the strains we're growing. So if we wanted to spend more time harvesting, say once every two weeks, we could run about five 8 plant systems. There would also be more time needed in the veg room, cloning and vegging plants. Even if we were so inclined, we don't have the space for anything that ambitious. Doing so would take it from a part time to full time venture for both of us. We have enough room we could expand each of our current systems with 2 more pots but felt that was a bit more than we wanted to handle at harvest time.

If we wanted to hire trimmers, then the only limit would be the available space. There are some large commercial grows here from several years ago when this sub forum was started. Some used to be in the Stickies until they were recently removed. I remember one, which if memory serves me, was about 40 plants, 10 tons of A/C and a shit load of both horizontal and vertical HPS lights. They had a 5 or 6 person team doing the harvesting and again, if I remember correctly, harvested the whole system in 24 hours. They are worth finding if you want to see a full blown commercial operation.

 

[Douglas.C]

The biggest issue I see with running a series of DWC totes is water chilling. I run a 1/10 hp chiller on each system. Trying to cool 16 individual totes would be hard to manage. How are dealing with this?

That's actually quite simple.
Cannabis grows super frosty, aromatic and tasty, with a 72F canopy temp. My 67-68F incoming air keeps the res at the right temp and it hits 72F by the time it reaches the top of the canopy. I flower in a very high transpiration environment, around 20% humidity.

I only have to be concerned with keeping the room temps correct, the res takes care of itself. :)

 

[RoeBuck]

I run light on at 78, so that wouldn't work for me. My water temps are right around 68. Keeping my room at 72 when the lights are on would add significantly to my A/C costs and eventually exceed the added cost of a turn key RDWC vs a DIY DWC system. Since I'm running a combined veg/flower environment I strive to keep my rH at 50%. (Air is pulled from my bloom room, through my veg room, back into the bloom room.) Going lower would require a lot more dehumidification than I currently have, again adding to both the startup and operating costs.

 

[Douglas.C]

I run light on at 78, so that wouldn't work for me. My water temps are right around 68. Keeping my room at 72 when the lights are on would add significantly to my A/C costs and eventually exceed the added cost of a turn key RDWC vs a DIY DWC system. Since I'm running a combined veg/flower environment I strive to keep my rH at 50%. (Air is pulled from my bloom room, through my veg room, back into the bloom room.) Going lower would require a lot more dehumidification than I currently have, again adding to both the startup and operating costs.

Yep, super trichome dense cannabis is expensive to grow in some areas of the country. I used to grow in hot desert climates, now I live where it's cold and dry. I can run active air for nearly 8 months of the year, sometimes more.

Douglas

 

[UCMENOW]

"Secrets to Trichome Dense Cannabis" By Douglas Curtis

Running with no chiller, standardized water chemistry in stagnant DWC seems reasonable for getting things done if this is your only option. Advising others to do the same as an optimum approach seems misguided.

Do it better and get better results.

 

[Douglas.C]

"Secrets to Trichome Dense Cannabis" By Douglas Curtis

Running with no chiller, standardized water chemistry in stagnant DWC seems reasonable for getting things done if this is your only option. Advising others to do the same as an optimum approach seems misguided.

Do it better and get better results.

Stagnant? Anyone running stagnant DWC deserves the poor results they get.
"R" doesn't necessarily mean non-stagnant either.

People either do it right or they don't. Only a few work to improve it to the best they can. Sounds like you've put a lot of work into making it work for you. Kudos. :)

 

[Midwestjay]

Chillers are a lil over rated imo Not saying they don't improve results but with tons of water/air flow and hydroguard you'll have crazy healthy big ass roots and plants to match.

 

[jumpincactus]

I've found all strains (so far, in 15+ years) to handle a full 7-10 day pH swing of 5.4-5.8 perfectly well. Not a single variation. I've also used lucas and then a modified lucas formula (and res management methods) throughout all those years.

So perhaps more 'balanced mix' dependent?

Good point. Do you have any experience with Jacks formula's for hydro? I have been considering giving them a go and would appreciate any input you may have if you have used it. Or I can run a search and see if there are any Jacks threads. peace

 

[Savage Henry]

Good point. Do you have any experience with Jacks formula's for hydro? I have been considering giving them a go and would appreciate any input you may have if you have used it. Or I can run a search and see if there are any Jacks threads. peace

Cap has an old grow log on here where he runs jacks in a rdwc I beleive.

 

[jumpincactus]

View attachment 622562 Chillers are a lil over rated imo Not saying they don't improve results but with tons of water/air flow and hydroguard you'll have crazy healthy big ass roots and plants to match.

Ya know with a rootball and good color that I am seeing there may have me doing a back peddle and apologizing to you when we dickered over rez temps a wile back. What is your rootzone temp without a chiller? Damn if you can get healthy growth like that with what your doing with your system at higher temps than what we are all told I could save some $$$ not stressing so much to keep shit perfect!!! so you say all you do is use hydroguard and again what are your highest rez temps in summer months? Peace

 

[jumpincactus]

Cap has an old grow log on here where he runs jacks in a rdwc I beleive.

Nice, good lookn out. Will chase that down.

 

[Midwestjay]

Ya know with a rootball and good color that I am seeing there may have me doing a back peddle and apologizing to you when we dickered over rez temps a wile back. What is your rootzone temp without a chiller? Damn if you can get healthy growth like that with what your doing with your system at higher temps than what we are all told I could save some $$$ not stressing so much to keep shit perfect!!! so you say all you do is use hydroguard and again what are your highest rez temps in summer months? Peace

Lol thanks brother. And that was after sitting a day or two after the chop. They darkened up a lil bit. But thanks again bro. I try to only speak from experience.

Just hydroguard, 1 975gph air pump, and res temps on that plant topping out around 82℉. Temp would swing between 75 and 80 usually.

For the last 2 cycles I haven even used res thermometer.