An experiment in SWC - Shallow Water Culture

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Limoges_Farmer

Limoges_Farmer

Chances are, if you're reading posts in this section, you're somewhat familiar with DWC (Deep Water Culture) growing. Typically, we're talking 12 inches of water or more, and with or without recirculation between the growing pod and the main sump. In shallow water culture, we have 3 inches or so of water, so I am guessing oxygen and lots of recirculation is going to be the key.
My plan:
Mother room: a 5 foot x 3 foot mother room now has about 10 plants in it. Some are there for sexing (take a clipping and flower it to see what the sex is), and will be going outdoors to either breed new seeds or for my outdoor crop.
Cloning: I just made a 77 site bubble cloner. It's a Home Depot tote with about 80- Liters of water (apx. 21 USG) and I placed some 3/8" think coroplast with 2 inch holes drilled about every 2.5 inches. I got 11 columns of 7 plants to fit nicely. Inside it, I placed four 12 inch bubble stones and a 100W heater.I adjusted the Ph to 5.8, and I'm waiting for lights on in the mother room to start taking clones. I'm using the 2" neoprene pucks everyone is using for bubble and aeroponics cloners.

The flowering room is also 5 x 3, and has a 4 x 3 ebb and flow table on an old dining room table. Under it is a 55 gallon Home Depot tote that acts as the main sump. The stable is 4 inches deep, and I'll be keeping the water level at about 3 inches, so there will be about an inch of air gap under it. It's made the same way as the bubble cloner, but the holes are placed every 4 inches which results in a 9 plants per square foot spacing. This is a setup I've done before on a much larger ebb and flow table with good success back in the 90s. The plan is to start flowering the clones as soon as the roots are big enough - no vegetative cycle is necessary.
As the title says, this is an experiment. One of the experiments is going to be in the amount of time spent in vegetative lighting compared to output. I will be reducing the number of clones (thus increasing the spacing), as well as increasing the number of veg days. I will then compare outputs and total time spent to see what setup has the best annual output. The key here is that when you add vegetative growth to the cycle, you reduce the number of crops per year you can get out of it. However, I may be able to circumvent this by leaving the clippings in the bubble cloner longer, and adjusting the feed in the cloner once they are ready to plant. This will take a couple years to perfect, methinks!
I have a 12 port air pumps with a dozen 12" air stones on the flowering tables bottom. The table has the chanels in it that are handy to keep the air stones from moving around. The table is fed water through a Pex pipe that has holes drilled into it for aeration when it hits the water surface. The table has 2 overflow tubes: one at each end. I want to change this because I only want to draw from the other end, but my tube is too narrow. I need to find a way to increase the overflow tube diameter (need better fittings that may or may not exist, so I may have to rig something up with abs fitting and glue).
Under all this is the 55 gallon sump that is maybe 1/3 full when the table is not drained. when it is drained, it's about 2/3 full. I will have more accurate numbers once I get to starting the table up in a week or two (depends on how successful my cloning is). In the sump I have a nice pump that gives me enough pressure for those small holes to hit the water surface and create aeration. Also in it is a horizontally-mounted 200 Watt aquarium heater - I hope I can get the water warm enough: I'm having issues with the cold as this is in my cold storage room.

Lighting:
As a mod in a couple Facebook groups, I got given some lights from a couple manufacturers to test.
Mother room: I'm using a 300W Mars Hydro model TSW2000 QB quantum board, and I'm happy with the output and coverage. I'll do a full review later on, as is my agreement with the manufacturer. I need to reposition it, and I'll do that this afternoon when I pull all the plants out for the first clipping.

Cloning machine: 2 fluorescent bulbs (apx 16 inches long), one has full spectrum with red and the other is more in the whites for daylight. The two together should give me quality light, but not the intensity. I may need to buy a light (probably a 100 Watt version of the flowering lights - see below).

Flowering room: Here I'm using 2 Viparspectra P1500, 150 watt quantum boards for a total of 300 watts input. I like these ones over the MArs Hydro lights for their heat rejection, sturdy body, silicone protection, and a true dimmer with knob. I want to use this for my cloning machine because of the ability to dim it and then increase the light as the plants mature.

Future:
Running air pumps 24/7 is noisy (not that much of a concern because of the location), and uses energy. I was thinking about taking the return water from the table and injecting it through a venturi that sucks in air. those can be very effective. I was also thinking about doing that in the table instead of the water jets: then I wouldn't need 2 pumps. I'd just use the one I have right now and accomplish the same task without using more electricity (a huge concern when doing commercial indoor cultivation of any kind).
 
Limoges_Farmer

Limoges_Farmer

The mother room.
Unfortunately all my videos are too large to upload here. Maybe I'll set up a YouTube channel and link them. What do you guys normally do for videos?
 
Limoges_Farmer

Limoges_Farmer

9 days later:

An advisor told me that I shouldn't have added nutrients to the water. He said that of s clipping is given everything it needs, it won't grow roots searching for food. This was Friday, so on Sunday adding no signs of roots, I terraced the water.

I didn't have any anchoring the air stones so they ended up bunching together. I had 2 bricks to anchor then, and filled up the 80 L reservoir, and adjusted the ph to 6.0.
Yesterdsy, I realized my water temperature was 24.5°C of 18°C that ok wanted. Instead of just adjusting the heater control, I replaced some of the water until I got it down to 18° C. Then I checked my ph, and it as at 7.0! I didn't come up with a reason, so I lowered it to 5.9.
This morning it was 6.8... So I adjusted it again, scratched my head, then it dawned on me that it must have been the bricks since the lack of nutrients shouldn't result in the ph rising every day. I'm assuming there's some lime in the brick, and it's leeching out into the water.

I replaced the bricks with a plastic bottle with weights in it. Hopefully this will work.
 
Limoges_Farmer

Limoges_Farmer

We got roots!
So 4 days after I change the water to pure ph'd water, I FINALLY got roots. That's 11 days from clipping. In thinking that if I hadn't fed them in the beginning, and I had my temperatures correct, I would have seen roots in 5 to 6 days.

Now to perfect this process.


Not: I'm also making clones for my outdoor crop. Actually, I'm only making clones for that, and will be doing indoor flowing once I have my all the clones needed for me and 5 other growers. That's around 30 clones of various strains.
As I have to sex some plants (7 Maui Waui seedlings/ plants, I wee taking clippings, rooting them with tug idea of plumb them in the flowering chamber to sex them.
A friend told me all he does is posed s dark cloth bag (Crown Royal bag) over a branch and checks it daily until he sees signs of a sex.
This process saves a lot of time. Anyone else do this?
 

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