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by Bill

Comments on Parts

6:34 pm in Being a good member of this community, Getting Started, made from scratch (without a kit), Materials and Resources, Projects in Process, pumps, Version 3.0 Modular Airlift Columns by Bill

Hi everybody,

I’ve just about finished construction on a 2-column windowfarm, and I am just waiting for my seedlings to get big enough to put them in.  I’ll post some pictures when it’s up and running.  Anyway, I have some comments and reflections on the “official” instructions and parts list.

So, I followed the instructions pretty closely except for on two points: first, my windowfarm is suspended from a free-standing frame on casters (which doesn’t really affect anything), and I used a t-joint for the airlift system.  The t-joint (a.k.a. t-valve) design is really simple and easy to install and use, whereas I found the method(s) outlined in the instructions to be really complicated and, frankly, intimidating.  The fact that the size of the check valve included with the air pump determines some of the other parts is pretty inconvenient.  Anyway, I hope the instructions are changed soon to include this more user-friendly design.

Speaking of the t-joint design, there are some issues that I ran into with parts.  Mainly, I bought a t-joint off the Petco shelf with all three openings the same small diameter.  It’s made for three of the standard 1/4″ OD tubes that come with the air pump.  The problem is that this makes a bottleneck for the flow of water.  At least I think it’s a problem.  Brian White say’s that the airlift tube should have an ID of 1/4″ for optimal performance, and he seems to have done his research.  I ran the 1/4″ OD aquarium tubing from the reservoir bottle to the t-joint, and from the t-joint up to the bottom of the 3/8” OD 1/4” ID rigid tubing from the parts list ( #9245K17).  It works, but maybe it would be better if I had bought a wider t-joint and used wider tubing.

Speaking of things that could work better, there’s the Petco pump (#9902).  It’s not adjustable, as far as I can tell.  I guess I can add a little adjustable valve in the airline, but if I throttle it that way I’ll be wasting energy.  I think an adjustable pump should be recommended.

Then there’s the tubing.   Two kinds of tubing on the parts list reference McMaster part numbers, but the 3/8” ID flexible vinyl tubing for some reason does not.  Now, McMaster has a ridiculously extensive selection of tubing, so we should be able to find one that works.  I used #5103K36 (Chemical-resistant Clear Tygon Tubing, 3/8″ Id, 1/2″ Od, 1/16″ Wall Thk).  It was okay for joining the two long pieces of rigid tubing, but it was not flexible enough for the top, to curve down into the top bottle.  Technically speaking, the “bend radius” is too big.  Maybe #5231K185 (Clear PVC Tubing Chemical, 3/8″ ID, 1/2″ OD, 1/16″ Wall Thickness) would be better.

Chains.  I think the ball/bead chain is a good way to go, and McMaster was a convenient way to order it.  Weirdly, though, the part number on the parts list (#3606T16) turns out to be stainless steel chain, whereas in the instructions photos it looks like they’re using plastic.  It’s not important, but what’s up with that?  I also ordered the specified couplings (#3606T41).  They are listed in the McMaster catalog as being the same size as the chain, but for some reason the chain does not fit through the center hole.  I had to widen the hole.  I’m not sure what to suggest here.

I think that’s everything.  I don’t mean to complain; I think the design is great and I really appreciate having access to it, but I want to help make it better and easier for windowfarmers who come after me.  I hope this post is the right way to give this feedback.  Sorry it’s so long and boring!




Four column window farm with T-Valve in Germany

4:10 pm in Completed Window Farms by Ingo Schommer

More infos on my blog

How to set up a t-valve airlift.

1:52 am in How-Tos, made from scratch (without a kit), Materials and Resources, posts with pitcures!, Version 3.0 Modular Airlift Columns by Kevin Wells

First, some background. This is my first window farm. I have no prior experience in hydroponics, but have grown many aquatic plants. I started making a DIY window farm following the directions of a single-column, 5-bottle hanging V3 window farm. I found that the bicycle needle airlift method just was not as reliable as I had hoped. It would sometimes work, and other times, I would find it not working at all. I researched the site and found that others had set up a t-valve airlift, and it seemed like the way to go. The other guides did not seem to include all the information I needed to get it set up for myself, so I decided to try it anyway. Below, I’ll tell you what I used. I will also say that if this method seems ridiculously simple and it looks like it’s so short that I might be missing something, it’s because it is ridiculously simple and I’m not missing anything… I think.

Parts needed (in addition to the other parts used for the V3 hanging window farm):

Standard aquarium airline. I went with black silicone, because it looks nice and will stop algae from growing in the airline. I bought 25 feet, because it was cheap and I will probably use more when I add columns later.

T-valve. I purchased a metal t-valve from PetSmart. They have plastic ones for even cheaper.

Silicone glue. You want to make sure you get silicone glue that is 100% silicone. I got mine at a hardware store, but they also often carry this at pet stores/fish stores (for aquarium repair). The 100% silicone will ensure that there are no additives that could leak into your water and plants.


Steps taken to add the t-valve airlift to my V3 hanging window farm:

  1. To make the sport cap airline connector, first insert 1″ of airline into the sport cap of the water reservoir.
  2. Inside the sport cap, use the silicone glue to glue the airline in place. Make sure to form a complete seal. It must cure for at least 3 hours before you can get it wet. I recommend you let it cure for 24 hours before doing anything else with it.
  3. Measure/cut 1.5 feet of airline from the cap, and connect this to one of the two straight ends of the t-valve.
  4. Connect your airline from your air pump to the perpendicular end of the t-valve.
  5. Using your remaining airline, connect one end to the remaining straight end of the t-valve.
  6. Run this airline to the top of your window farm and into the top bottle. Secure using zip ties or what ever you prefer.
  7. ???
Important note: You can’t see it in my photos, but my air pump is elevated above my water reservoir. This guarantees water will not siphon through my air pump, and negates any need for check valves. If your air pump is lower than your water reservoir, use a check valve on the airline coming from your air pump to the t-valve.

Look at my awesome diagrams:

I almost forgot to give credit where credit is due! Brian White, aka gaiatechnician, has very helpful videos on Youtube and his diagram helped me get started. Granted, I tweaked it to work best for me.