I posted earlier about designing a prettier window farm. I’m now building a clean and simple single column farm, and I figured it might be about time to post something about my progress. The pots, suspension and drip pipes are mostly in place. The reservoir and the airlift are still in the works. I haven’t made up my mind yet about what kind of reservoir to use.

Part list:

• 4 Plastic orchid pots. These are made of Polypropylene, which is (afaik) safe to use with food. The pots also have an inward dent in the bottom, so they will never drain completely. I don’t know whether this is a good thing or a bad thing. Be careful when drilling plastic. I managed to break one pot by using too much pressure. (2 euros/pot at Bauhaus)
• 2 meters of aluminum pipe, 6 mm diameter. One meter for drip pipes and another for the air lift. (4 euros/meter at Bauhaus)
• Two meters of aluminum strip. Mine is about 12mm wide and 2mm thick. I wouldn’t go any thinner than 2mm, since the rigidity of the column would likely suffer. (4 euros/meter at Bauhaus)
• 4 gaskets for sealing the drip pipes. The ones I got seem to do the job pretty well: 17mm outer diameter, 5mm inner diameter, 4mm thick. (around 2 euros for a 4-pack)
• M3 Nuts, washers and screws (or bolts) for attaching the pots to the aluminum strip. (Less than 1e total)

Parts not installed yet:

• Sera Air 275R Plus air pump with adjustable air flow and two outlets. Came with two non-return valves. (28 euros at a local aquarium store)
• 6mm “colorless” air hose. It’s possible to stretch this over the aluminum pipe using pliers and some soap as lubricant. (2 euros / meter at a local aquarium store)

Still missing the reservoir and the airlift needle(s).

This is not the final assembly and you might notice that some of the drip pipes and pots are not straight. I’ll fix that before doing the actual planting. Originally I’d thought I’d have to glue the drip pipes to the pots, but with the gaskets in place and the hole being tight enough, I’m not sure if glue is necessary. It won’t matter anyway if the drip pipes are wet on the outside.

I was wondering though, should the downward water flow be somehow restrained so that the water drips down slowly? Now when I pour water in the top pot, most of the water has come down in less than a minute. How does it work in WF 3.0?

The wife said it looks alright. I might even get a permission to build a second column Stay tuned. The next step is building the airlift.

Hi everybody !

It took me a couple of weeks of thinking, and a whole weekend to work out everything, but there it is. My sailboat windowfarm is now working on a regulated dripping system since… 5 hours. This one is not plastic-free, but it is electricity-free and if everything works out as planned, the dripping flow will be entirely automated… in between the moments I choose to close it (since there is no timer either on this installation).

By the way, Brian, I tried twice to send you a comment on your last post (Easy way to attach a T-Joint…), because I had a few questions, but nothing would pass. I posted another comment to someone else and it passed. So I don’t know what I did wrong or if you blocked the receiving of comments by mistake. Anyway, thanks a lot for your explanations and drawings. It made things a lot easier.

I’m still looking for a mainly non plastic dripping system for my clay pot windowfarm, so I may come back to the emitter valve (if I can find one somewhere) and glass or metal containers, but this one is my practice, servicing my all plastic sailboat windowfarm.

Photo 1 : While looking for an emitter in my local hydroponic store, the salesman directed me right to this product (which is intended for animal water tanks). At 22,99$ (Canadian), I couldn’t resist long, as he didn’t have the emitter and didn’t seem to know exactly what I was talking about. It ressembles a toilet float valve, only much more compact. The brand name is Little Giant, item number TM825, by Miller Manufacturing co. Glencoe, MN.

Photo 2 : Here’s one of the plans provided with the thing. It’s easy enough to assemble. You fix the red floater to the black housing with a “cotter pin”, you tighten your brackets to the black housing with two short screws, and later, you use two long screws to thighen the whole thing to the side of your reservoir. You have a washer to put down into the mouth where a garden hose will be screwed up (standard 3/4″).  That’s about it for the stuff provided in the box.

Photos 3 and 4 : I still needed other components though. I spent another 10 box on the rest. As I wasn’t just about to use a 10 foot garden hose, I needed to mount one much shorter. So I bought an adaptator (on photo 3, it’s the grey plastic part just under the yellow hose) between the 6″ bit of yellow garden hose that I used and the float valve (in black), and then another adaptator (on photo 4, it’s the black part) between the upper reservoir (a cheap plastic container that I had to pierce a round hole into) and the garden hose. Finally, I placed two of these plumbing metal necks (I don’t know their name in English) over both junctions to insure watertitghness. By the way, the green electric wire is just there to keep the garden hose bent down, because I was tight on vertical space. I only had 12″ vertical clearance. Now that the hose adapted in it’s place, I won’t need the wire anymore. With that bent in the middle of the garden hose, I was afraid to block the water’s flow, but thankfully, it just slows it down.

Photo 5 : I used a flimsy plastic container made of half a kitty litter container. It doesn’t show on the photo, but I put a small piece of wood between the container’s exterior side and the float valve brackets so both long screws could set onto it. It makes everything more tighten at the same time. The container is only 4 1/2″ deep. I think it’s just the minimum to make the float work properly (if you don’t need a fast refill).

Photo 6 : Here’s a view of the whole installation. the principles are quite simple. You have two reservoirs, one on top of the other. The upper reservoir will empty out gradually. The bottom reservoir acts like a buffer, because the float valve regulates the intake of water and keeps this reservoir always at the exact same level. This way, the water pressure in the bottom reservoir is alway the same, so you can adjust your dripping valve once and the water flow will remain constant until your upper reservoir is empty. In that event, the float valve reservoir would then start to empty itself and from that point, your water flow would not be even anymore, slowing gradually. One end of my drop-by-drop tubing is maintained at the bottom of the reservoir with a rock, just like in the previous system. The tubing runs over the edge of the tank, so I didn’t have to pierce any hole to drive the tubing through the container’s side. It lowers the risks of leaking, which is to greatly please me, considering the position of all this water just above my dictionnaries LOL ! The white plastic bottle neck is simply a piece I cut out and squeezed under the black float valve to stabilize it. It doesn’t get in the way of the red floater (which you cannot see on this photo, because at that moment, it was in its upper position, inside the black housing, shutting the flow of water).

There’s at least one drawback on this installation : it won’t be that easy to dismount it to clean up every component. I could not find the proper parts that would have allowed me to separate the two tanks in a jiffy. I tried with metal garden hose connectors, but it kept leaking, so I brought everything back to the hardware store to get a refund.  Next time, maybe ?

Photo 7 – 8 – 9 :  To make the installation a little tidier, I used an old wooden crate to put the float valve reservoir in it. It also acts às a support for the upper reservoir. It’s too long for nothing (about a third too long), but it’s 12″ wide, just the exact depth of my shelf. My instatallation is barely under 12″ high, so it almost scratches the upper shelf. But I can draw the whole installation a little outward (so it sticks out about an inch) and it becomes very easy to refill the upper reservoir (photos 8 and 9).

Photo 10 : A view of the whole thing. You’ll notice that my highest bottle is at least a foot lower than the shelf where the float valve reservoir is sitting. I think it’s the reason why I can get away with the water pressure given by less than 2 ” of water depth in that reservoir. Otherwise, the resistance in my tubing would be too high to let the water flow freely, possibly. It would be different if my reservoirs would be directly over the windowfarm, but the ceiling clearance is not sufficient to allow me such an installation.

Just before publishing this article, I noticed that the drip rate is at roughly one drop every 4,5 seconds. Five hours ago, I settled it at one drop every 2,5 seconds, so it slowed down very gradually. But it’s my drop-to-drop ajustment valve that is the culprit, I’m sure of it (it’ this small white thing on the tubing, with a red adjustment wheel on photo 10). The water level in the float-valve reservoir didn’t move a millimeter. I’ll give you an update on that.

Hello!

I am very excited to set up my window farm!

I managed to play around with my air lift with a airflow valve, and I have quite a range of drips.

My question is how much water should I be cycling through my window farm in a given period of time?

Also, is it better to have a steady slow drip or to have the pump on a timer and just run the water at certain intervals?

Thanks for your help.

Melissa

So excited to find this group!

I’ve put together a three bottle system for my daughter’s room that uses an aquarium as the reservoir. For the actual farm as complete, I used under $25 worth of new parts:

• 3 CVS 1.5L Water Bottles (on sale for 3/$2)
• 10 ft 1/4″ OD tubing ($5)
• 1 ft 1/4″ ID tubing ($5 for the 10 ft length - I have excess left…)
• Air pump ($10 at the hydroponics store)
• 5 gal hexagonal Aquarium with under-gravel filter (free, was en route to be taken out to the trash)
• 2 goldfish ($1 since my daughter hand-picked, else $0.10 each)
• spraypaint (had on hand – painted each one black first, then oversprayed the black with white primer)
• 3 netpots (used the 3.75″ ones, $0.50 each from the hydroponics store)
• 1 empty children’s liquid tylenol bottle (free)
• Expanded clay balls ($12.99 for the bag at the hydroponics store, maybe used $1 worth for this setup)
• 18″ black cord (had on hand)
• 1 nail (had on hand)
• 2 ball inflation needles (had on hand, just bought 10 for $4 on eBay to replace what I took and prepare for future window farms)

You’ll see in the picture (will edit tonight to include) that I also used some double-sided velcro and bamboo stuff, but I consider that primarily decorative so didn’t include it in the cost. But I haven’t yet put in the one way doohickey to prevent water siphoning back to the pump, so that will be another couple of dollars.

I cut two rectangular holes in each bottle, which will allow two plants per bottle and made it easy to drill the 1″ hole in the bottom of the bottle. I could have gotten by with a 1″ drillbit and a 1/4″ drill bit. For finishing the holes in the sides of the bottles, I used a hole punch so the corners would be neat (and not “tear”) and regular scissors to make the rest of the cuts. The only other tool I needed was a tiny screwdriver, which I used to poke the holes for the ball needles.

I think I could have drilled the 1″ holes freehand, but I rigged up a wood jig that supported the bottle – another picture to add tonight… I also fastened the “silencer” bottle on the top of the group the same way the other bottles are fastened together. The “silencer” quiets any noise from the water popping out the top of the system, and creats a “finial” effect that is esthetically pleasing. A nearly-vertical nail in the window frame and a piece of cording around the neck of the “silencer” are used to support the load of the system.

For the drip, I couldn’t quite wrap my head around the standard instructions. But I liked the description where folks used the ball needles to inject water into forced air, rather than forced air into water. So I did it that way, stuffing the tubing down into the cylinder coming up from the under-gravel filter.  The system gets a good drip on a continual basis and it’s no more noisy than a regular aquarium set-up would be.

I’ve transplanted some basil and parsley into the two top bottles and plan to put strawberry plants in the lowest bottle.

In the mean time I’ve got some okra, lettuce, and cherry tomato seeds germinating in rock wool for a future window farm in my other kid’s bedroom…

Finally sufficiently done with our aquaponic windowfarm to post a youtube tour of our set-up:

http://www.youtube.com/watch?v=8zq7T6QNrc4

It’s taken a bit of investment to get to this point, but I think I could pull one of these together for $40 (a bit more because of the fish aspect), and last weekend we gave one of these as a birthday gift to one of my pre-teen’s friends.

I’ve got two kids with good windows for this, so will post another video when I get the second windowfarm up and running.

Innovations:

1. Used an alternative method to perform the airlift, based on a post I saw here – my lift uses the ball inflation needles to inject water into the air hose instead of the other way around.
2. I use the “silencer” at the top of the drip line to support the weight of the assembly. It serves a decorative purpose (finial) and makes it crazy easy to support the whole assembly from a single near-vertical nail in the window casing. I don’t need to use any other supports given the exact 1″ hole I was able to drill into the bottom of each bottle.
3. I used double-sided velcro strips to fasten the tubing going up.
4. I used a 1/4″ OD tubing (short length, angle cut on exit) to control the drip. Don’t actually know if that’s a great idea, but I didn’t want the water splashing the windows and some plants supposedly don’t like getting watered “directly.”
5. I just use 1/4″ OD tubing from the lowest bottle to guide the return water back to the fish tank.
6. I use one of the variable control air splitters to ensure both the air lift and the air stone get enough air pressure.
7. I used a hole punch to round the corners of each “grow hole,” of which I cut 2 in each bottle. The “square” holes allowed me to get a jig into the bottles for a nice drilling support, so getting the 1″ holes drilled in the bottom of the bottles was a breeze.

We’ll see in a few weeks whether some of these “innovations” were really dumb ideas…

I’m attempting to build a version of the Airlift Window Farm without plastic parts.

The initial version uses stainless steel tumblers, sisal rope, metal crimps, a glass reservoir, and natural latex tubing. The only plastic part is the air pump. Everything was purchased fairly inexpensively (mostly on the Bowery in NYC).

You can find images of the project in progress HERE.

If I can get this one to work, I will build a second system next to this one using Chinese bottle gourds, coated in beeswax (see diagram). We’ll see.

PROBLEMS:

1. I’m currently having problems getting the pump to push the water up the airlift tube. I’ve noticed others have had this problem and see that Britta posted some suggestions, which I tried– but they haven’t worked. The air forced into the air lift tube doesn’t seem strong enough to move the water up vertically. It goes for about 6 inches and falls back down again. It also makes a loud bubbling/spattering noise. The pump tubes are dry and the air lift tube is fully submerged and mostly straight. I have an ActiveAqua AAPA7.8L pump. — ANY SUGGESTIONS?

First, try adding a one way air valve to each of the tubes on your system. They come with the petco pumps. Otherwise, they are about $2 at an aquarium store.

Second, make sure your tube is submerged under as much water as possible. If it is curling back up on itself and is therefore only a few inches below the waterline, attach something rigid to it.

If that isn’t the whole problem, try this. Take the whole Airlift tube system out of your bottle. Detatch the needleside portion of the air tubing from the little one-way valves. Blow through those air tubes to clear all the water out. Maybe leave it out to dry and if you see any waterdrops in the line. You want to try to dry out the air tubing part of it and have air pumping through it before you stick it back in the pre-filled bottom water bottle.

Here’s the logic. Water is going to want to get in to the air tubing through the needle. If it does, that water is a lot of extra “weight” that the pump has to counteract to get it’s air out of the tube before it even makes it to the needle. So dry that tubing out and then only reinsert those “guts” after you have hooked it up to the pump and the pump is on. This way it is always blowing air out so water can’t get back in.

We are building the easier three bottle window farm, and have put it together according to the directions, but aren’t getting a drip!

Should we make sure the needle entrances are properly sealed or make a smaller drip exit?

Help us out!

Sami

This system can churn-out a salad per week, but it is definitely not the place to start if you are a beginner. This was our community’s first design and is a little more of a challenge. The window farm described in this How-To is a reservoir system. A water pump on a timer periodically pumps water and liquid nutrients from the bottom reservoir to the top reservoir. There are small holes drilled into the underside of the top reservoir. Small drip emitters with valves let out a constant drip of water and nutrients into a column of plants. Each plant sits in a grow medium in a net cup (a perforated plastic cup commonly used in hydroponics), within an inverted plastic water bottle. The cap of each water bottle has a hole in it so that the water and nutrients can drip from one bottle to the next, from the top to the bottom of the column of plants. The bottom-most bottles are connected to tubing that takes the water and nutrients into the bottom reservoir, where it sits until the pump turns on again.

Water pump systems are a little more finicky and are susceptible to clogging. Most of the community has moved toward the airlift design so unless you are very comfortable with tools and handy, we suggest trying the airlift how-to.

IMPORTANT ELECTRICAL SAFETY UPDATE!!! Please remember to include a drip loop on electrical components of this system. Make sure the cord hangs down below the outlet and then goes back up to plug in. Make sure you do not have an outlet directly under your reservoirs.

Download the PDF of the How To instruction guide here. Please note that we ask anyone who downloads the how-to to register on the site and to come back and post as you build, not just when you’re finished. You give back to the project by participating on the site. Bring questions, ideas, results of your testing various processes. This is a mass collaboration on the R&D of these systems.

Britta and I finished the first window farm prototype in her kitchen window in April. The system includes a pump in a bottom reservoir which is on a timer, to pump about 3 gallons of water/nutrient solution up to the top reservoir. The liquid then drips through the columns of water bottles that hold the plants.

We’ve listed each component below, and some of the lessons we learned.

The main components are:

• Reservoir 1 (a 5 gallon bucket on the floor)
• Water pump (orange)
• Reservoir 2 (a tupperware container on a shelf above the window)
• Large diameter tubing going up to fill Reservoir 2 (orange)
• Small tubing to and from each vertical component
• Clamps
• Water bottles
• Net cups with clay pellets
• Covering for roots
• Fishing Wire to suspend
• CFL bulbs and covers
• Light Timer
• Air Pump
• Second timer for pump

Scroll down for more details about each component. We have listed each component and ordering information on this site.

Reservoir 1 is a 5 gallon bucket on the floor with water and nutrient solution

- 500+ gallon per hour pump of high quality which makes it quieter. You can go with a cheaper one if like this it will only turn on 3 times a day.

- There is a timer on the pump which turns on for 2 minutes every 8 hours. It fills Reservoir 2.

- Along with the pump, the reservoir also has an aquarium air bubbler in it to keep the water aerated or moving so it does not stagnate. This thing is a problem because it is loud. We should find quieter ones because it stays on all the time.

Parts in this area:

• 5 gallon bucket
• Water pump (500 gph)
• Timer for pump with at least 3 on/off settings per day
• Aquarium air bubbler and airline tubing
• Tubing that fits water pump fitting (to go to reservoir 2)
• Extension cord
• Nutrient solution mixed with water

Reservoir 2 above the window

- The reservoir is filled via the tube coming up from the pump in reservoir 1. The size of the tubing was determined by the fitting on the pump.

- The reservoir itself is a tupperware container we got at the hardware store. In the future we would look for something made out of thicker plastic so it is easier to put the plumbing connections into. This plastic was thin and difficult to drill clean holes into. Also, technically this should be an opaque container since nutrient solution should not be exposed to prolonged light, but we choose clear so we could see the nutrient level and color.

- We used brass pipe fittings to connect the tube to the reservoir. They included the barbed brass and yellow rubber you see on the right of this photo. You cannot see the other side of the fittings, where we used the female pipe fittings to tighten the connection on the inside of the reservoir.

- There are 5 tubes which come out of the reservoir.

- They are clamped down really hard so that the 3 gallons of water in the reservoir takes the whole 8 hours to drip through the system – so the plants are getting a constant drip.

- We’ve realized now that instead of clamping, the better solution would be to use much smaller tubing – probably 1/8th inch – to slow the water flow – instead of needing the clamp the tubes.

Parts in this area

• 5 gallon tupperware container with lid
• Shelf and brackets to mount container on above window
• Barbed connectors to connect reservoir to tubing to plants, rubber O-rings and aquarium sealer
• Clamps (although these might not be necessary if your tubing is much smaller than ours)

Water Bottles

- The five tubes from Reservoir 2 extend into the top water bottles.

- The water bottles are suspended by 15 lb fishing wire tied to simple hooks drilled into the top of the window.

- The plants are in net cups, in clay pellets, resting in the water bottles, which, because of the ‘eco-shape’, are the perfect size for the net cups.

- Some of bottles have their caps on, with some holes drilled in the caps for the water to drip through. Another design we experimented with here has plastic martini glasses duct-taped to the bottles which have had their tops cut off.

- The water drips down through each plant and then to this tubing at the bottom, which brings the water solution back to the bucket reservoir.

- 6 100 Watt CFLs from Home depot in normal sockets. This may be overkill. However, in general the closer you can get the lights to the plants the more growth you can generate.

- Light Timer with 5 sockets goes on once a day and turns off once a day

These are some of the things we would change in the next version:

• Find better plumbing components
• Ian suggested using a chin up bar to suspend everything from at the top of the window to not have to drill the hooks
• Gabriel points out that a cheaper alternative to a chin-up bar might be some threaded pipe from the hardware store. They sell metal pipe cut to length and threaded on the ends, which screws into plates that are screwed onto the window frame. So some holes in window frame, but only in two places vs. a series as with hooks. Very strong.
• Remove the reservoir at the top and experiment with the pump so the water can go directly to the plants
• Play with the lighting design so less light bleeds into the apartment and out the window
• Find more flexible tubing for the bottom so that there’s not that large tube going to the reservoir
• Use containers other than water bottles
• Find a way to use coconut coir so it doesn’t clog the system
• Look into using copper
• Pump- cheaper? Non-electro?
• Air pump- quieter? Non-electro?
• Tubing adapters- easier?
• Reservoir 2 attachments
• Root covers- elegant?
• Containers- alternatives, less labor
• Wiring- Less messy
• Clamps- cheaper
• Suspension- Less invasive, more stable
• Aeroponics?
• Microgreens setup?
• Lights- positioning? use less light by sensor switches? filtering less harsh on eyes inside? less light pollution outside?