So I'm planning my 1st rdwc. I want to start with 5 17g totes a DIY water chiller from a old freezer. Can anyone point out some flaws or improvements to the design. I plan on 3" return lines between totes and back to DIY chiller and 1/2" or 1" feed lines to water falls in each tote. I'm offsetting the return lines to create what I think will be a swirling effect. I think I'll be using atleast a 1000gph pump to make it all work. Please dont state the obvious by saying buy a chiller.
1st RDWC build
- Thread starter Rdot03
- Start date
MoodyShoes
Well-Known Member
Seems over complicated to me.
How many grows have you done before this one?
How many grows have you done before this one?
Airwalker16
Well-Known Member
You'll see why buying a chiller is what you'll end up doing eventually on your own.
5BY5LEC
Well-Known Member
Yea hopefully I'll be able to afford it next go around. You think a 1k water pump will work?
Over complicated how?
JSB99
Well-Known Member
2" pipes would work fine, and it would save you some $$.
Don't do the swirly thing, by offsetting your pipes. Keep everything inline. You'll lose lots of circulation with the layout you're proposing.
You're shooting in the dark with regards to the water pump size. What is your goal, an RDWC, or an Undercurrent? With an RDWC, you would be using an air pump to deliver dissolved oxygen to the roots, and more importantly, the center of the root mass. You'd use a lower flow water pump to recirculate the water. If you're wanting to build a UC, you need to calculate the size pump you'd need to circulate the total number of gallons, 12 times an hour. Reason for this is to ensure that there's enough flow to get dissolved oxygen to the dense parts of the roots. Simply having a waterfall on each tote doesn't get that done. With an air pump and stones, the massive amount of bubbles under the root mass does this really well.
An important note, since you are debating a chiller, is that, the larger the water pump, the more heat you have to fight. Undercurrent systems require larger pumps, which makes this battle tougher, as well as more expensive. With my RDWC, I don't use a chiller, and I'm able to keep my water temps as 68 to 70, with just some easy, creative ducting.
I've read I can use waterfalls to get rid of air stones. Outlets in line make sense. So a mix of the 2 systems I'm going for. I thought res needed to be around 60 degrees? Also running inline pump.
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JSB99
Well-Known Member
It's not a direct trade-off. You can replace your airstones with waterfalls, as the method of adding dissolved oxygen to the water, but you still have to have a way of getting that
DO through the roots. Roots not getting oxygen will cause a lot of major issues, which is why it takes a lot of force to get to the denser parts.
As far as adding waterfalls to each tote, it's overkill. Adding a single waterfall, with a foot of drilled PVC to spray it, will add all the DO you'll need.
If you run an RDWC, you can get yourself a smallish 500gph pump to circulate all the water. I keep around 55-gallons in mine, and use a $25 450gph water pump.
68 to 70 degree water helps me to go a full grow with no flushes, keep white roots with no additives, keep the water from smelling, and helps me prevent root rot and slime. I wouldn't bother dropping below 66 degrees. And, if you can avoid a chiller, it's so worth it. They're expensive.
Take a look at my thread if you want to see how I did mine. Thread
GBAUTO
Well-Known Member
My 4-17 gal tote system uses 2" drains and a 3/4" return on a 700 gph pond pump. I don't run a separate rez and I haven't used a chiller for the past three years. Although it's possible to operate without a chiller it was always a waiting game for disaster. System volume is right at 40 gals using 6" netlids and the only thing I had to do initially was to tuck the root ball under itself so it didn't flow into the drain pipe. After that, it was just monitor and replace the fluids. I agree that simple is always the best solution.
https://drive.google.com/open?id=12vWK-Ie1a8T9UWxBiFsODC2jb0bpvG8J1A
https://drive.google.com/open?id=12vWK-Ie1a8T9UWxBiFsODC2jb0bpvG8J1A
What cobs you running
MoodyShoes
Well-Known Member
GBAUTO
Well-Known Member
My fixtures started as 4 Vero29's on a 320w driver. I added 35w of 660nm as well a 120w of Samsung F strips during flower-it's a bit of overkill but it grows some serious dank.
https://drive.google.com/open?id=18gxGrtmRvJvRhjrWkt3ryp9lwzMLbhsDAw
p.s.-DIY sometimes means fixing your errors as you go. Had a wiring failure(self induced-doh!) on one of the cob deep into flower, colas wall to wall. Kinda difficult for this one-legged, one functional arm guy to navigate when it's accessible so the 'emergency' wiring repair is the reason for the wiring mess.
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I'm going to build a vero29 fixture too. I'm excited to get started. I got my heatsinks from alibaba
5BY5LEC
Well-Known Member
So, your saying that a single waterfall in the control bucket will aerate the system well enough on its own, provided the water circulation is powerful enough to circulate the oxygenated water quickly?
5BY5LEC
Well-Known Member
I used to love my air pumps and stones but after my last grow I realized that the biggest issue is not heat or D.O.......it's contamination from the air.
For that reason alone my next setup will be without an air pump.
Check out my rdwc in my sig and if you have any questions feel free to ask.
For that reason alone my next setup will be without an air pump.
Check out my rdwc in my sig and if you have any questions feel free to ask.
JSB99
Well-Known Member
Exactly, just one is the res. As far as the water pump, let's say you have a total of 100 gallons in your system, you would want to use a minimum of a 1200gph pump. More powerful is better, but at a cost of adding more heat. Something you can do to help is to have a small PC fan blowing on the pump. That way the heat isn't building up and going right to the water.
Keep all your 2" pipes inline so that momentum can build with the circulation through the totes.
JSB99
Well-Known Member
Never heard of that, but it makes sense, if there are contaminated in the air. Mine is in a bedroom, so the air is cycling through the air handler filters.
Keesje
Well-Known Member
I do know that most commercial hydrogrowers stopped using venturi's (they never used airstones anyway)
Not because of contamination, but because it brought to much CO2 in the water.
And CO2 can result in pH swings.
Just agitate the surface of your water and you will be fine. There is where the exchange between the air and water takes place.
5BY5LEC
Well-Known Member
Yeah for sure on the
At any rate, just having one spot doing the aerating would be awesome. A lot less piping.