Toilet Tank Bean Sprouter





Introduction: Toilet Tank Bean Sprouter

This Instructable is an improvement on a prototype like design that I submitted some time ago. See Semi-Automatic Hydroponic Planter/Sprout Grower. There were some inherent "problems" that I believe to have solved in one way or another. The biggest of which was access to the sprouts. This design has a completely removable grow chamber tub for easy filling/dumping/cleaning.

Having run for some time and not getting sick in the least after eating many harvests, I am satisfied that "I" will not succumb to any potential pathogens able to resist the frequent rinsing with chlorinated water. I'm still more worried about the door knob in any office building or coffee shop than "my" bathroom air. I can speak for no one else. I'm also more worried about the store bought, slimy, sulfur smelling, growth stunted sprouts/salads that come "fresh" in a bag.

If that still worries you, this unit could be placed in series with a drip as well. Anywhere, in fact, where there is a sufficient supply of safe water. A leaky tap (which should actually be fixed ya know), rain water, a stream or drip of any kind that can be fed into the top of the unit and supply coverage.

That being said, the new design incorporates a different and more convenient access grow chamber as well as superior, wall mount bracing. You're on your own if it's pretty you're looking for.

Step 1: What You Need

1 ea "Adjustable Height Wire Hanger Bottle Hanger"... see Wire Hanger Bottle Hanger... or other suitable support mechanism. See that instructable for a separate list of materials and tools and step 2 of this instructable for a photo.

1 ea 2L pop/soda bottle
1 ea 4 inch dia. margarine or yogurt container w/lid
1 ea toilet of the toilet optional...
Flexible tubing as req'd to interface with the tank hardware and create a sprinker/shower head inside the "grow chamber". Because I had a variety of tubing, I was able to something up using the following..... 2 ft of 3/8" OD vinyl tubing
4 inches of 1/4" ID x 3/8" OD polyethylene tubing (it's stiff and it melts to itself)
1 inch of 7/16" OD vinyl tubing (cut into 4 O-rings to act as ring clamps)
2 inches of 7/16 " OD vinyl tubing (coupler)

1/16" and 5/16" Drill bits
Pliers to bend coat hanger as req'd by mere mortals (2 pair)
Side Cutters to cut tubing

The need to flush at least twice a day doesn't hurt either. Actually, it's essential.

Step 2: Bottle Support Mechanism

Construct some mechanism which will support the "sprouter" a couple of inches above the max water level of your toilet tank. It is important to keep an open air space between the tank water and the bottom of the sprouter or the "drain".

I used the "Adjustable Height Wire Hanger Bottle Hanger" mounted on a 3/4 inch piece of plywood which is mounted on the wall just above my toilet tank. The plywood allows me to NOT destroy the wall as well as act as a spacer to better position the sprouter drain.

See Wire Hanger Bottle Hanger to construct unit shown.

Step 3: The Funnel

Cut bottom off bottle, with scizzors, near the lower label line so that it makes a deep funnel.

Step 4: Grow Chamber

Drill lots of 1/16" holes in the bottom of the yogurt container.

Drill one 5/16" hole in the lid of the container.

Step 5: HOSE

Make shower head by melting one end of the polyethylene tube and pinching it shut with pliers. I chose this tube because it is more rigid than the vinyl. It also melts into itself when heated, unlike vinyl, creating a more permanent seal at the end of the "hose".
Holding the tube, with pliers at the pinched end, drill several 1/16" holes through the tube in the 2 inches nearest the pinched end.

Cut the 1" piece of 7/16" OD vinyl tubing into four rings.

Onto the un-melted end of the shower head, slip two o-rings onto tube. Then slip tube through the hole in the lid and "lock" into place with the other two o-rings as shown.
Slip one end of the coupler over the exposed end of the shower head as shown.
Slip one end of the 3/8" OD vinyl tubing into the open end of the coupler as shown.

Step 6: Assembly

Place 2L bottle funnel into the holder.
Insert the grow chamber tub (yogurt container) into funnel.
Place lid on container and connect hose to tank water supply to redirect the flow through the sprouter.

Step 7: Operation

Fill tub with desired amount of desired beans or other sproutable foodstuff.

Flush away as usual for the required length of time.

Open grow chamber, take tub to kitchen, rinse sprouts yet again if desired, and enjoy.

Repeat as desired.

Mung beans are available at most bulk food stores, are cheap as hell, and take only three days to grow.



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    47 Discussions

    Just a little food for thought, flushing your toilet has the potential to release fecal particles into the air, which in turn could possibly contaminate whatever it is you are growing in this contraption.

    Google 'toilet aerosol effect', or follow the link below.

    1 reply

    That is what I was thinking you are right I saw this is on TV I am sorry but this is gross..

    I did this same thing but without the toilet.

    I made a knock off version on the sprouting device they sell at the sprout people web site. I used 2 plastic stackable cups with tiny holes drilled in the bottom of th inner cup for drainage. I used the plastic lid off of a jar of instant coffee for the lid after drilling small holes in it. I also made a supers router out of a couple of small (one or two quart) stackable sterelite stackable storage containers for larger batches










    What a fabulous idea for that spare bathroom that is only used a couple of times a day, and only by family. I can't say that I'd share the origin of my "toilet sprouts" with my dinner guests, but you're right, my doorknob has far more bacteria than these sprouts.

    1 reply

    Thanks. Yup... I'd be more worried about E-coli from a bagged salad, but just try to explain that to anyone, especially dinner guests. It's one of those things that just leaves a bad taste in their mouths. It's probably the lack of preservatives.

    Dam fine idea. If squemishness is a problem, couldn't you just build some sort of cabinet around the unit to hide it? I'll bet this is cleaner than the majority of produce you buy from the store.

    The water that goes into the toilet is the same drinking water that goes into your faucet and is no way any "dirtier" than the water that you use to drink and cook with. The crazy part is that we urinate and defecate in to perfectly treated drinking water. Wiley (the author) is putting this safe drinking water to better use before it gets contaminated with bodily waste. So, in short, yes this is edible.

    I don't think plastic from the cistern and the tube is food grade plastic though. They might have been treated with some kind of crazy chemical, or the plastic might be a crazy cehmical itself.

    Your concerns with potential chemical leaching is valid, and something that one should look into before taking on a project like this.

    Seriously?, you worry too much. if this perfectly good 'ible kills you, then you can complain.

    And yet people buy ground beef and poultry everyday ..... Sorry, no offense intended, but I get this argument a lot and I'm not sure why, all other things we do considered. Trust me, if you get ecoli, this is probably NOT the source. I do have to say that this method has produced the only sprouts that I was not worried about eating before rinsing BECAUSE there is NO sliminess or odor to them, at all .... I would normally use those as a sign of bacterial contamination. All other methods I have used have had obvious signs of some bacterial growth. They are enclosed and isolated from the tank itself. Other than that, your fingers and every door knob are more of a threat to your health ... IMHO. I don't get sick, except for the sniffles once or twice a year, so I'm not too worried.

    Hi and thank's! I've built up a real "Toilet Sprout Farm" starting from your instructable! Nice Job! You can see my re-edition here (yes... I'm sorry, just in Italian... but with few "good" pictures) ;)

    1 reply

    I love it!  Thank you for taking this idea and running with it.

    I didn't understand a word, but the pictures made me all giddy... much like National Geographic magazine when I was a kid.  :P

    No need to apologize for being a multilingual Italian... I'm a uni-lingual Canadian, and I'm not even good at mastering that.  I'm so ashamed.

    Great idea! With those that are concerned about appearance or mists of pee, you could always take the plywood backboard a step further and actually find or build a small cabinet large enough to cover the opening of the tank. This should enclose the rinsing unit, protecting it from possible contamination, cover the gaping hole and workings of the toilet, and still allowing easy access to the unit. Just a thought.

    Has anyone pointed out that the purpose of the water flowing out that little tube when you flush is to go down the overflow tube and refill the bowl; any excess just goes down the drain once the usual 'full' level is attained. There's a similar sink which replaces the toilet lid. Every time you flush, water flows out a small faucet attached to the sink. When the tank is full, the water stops flowing. The difference is the drain tube from the sink goes down the overflow tube. One can wash their hands withOUT turning water on (and touching the handles) at a conventional sink.
    I would recommend locating the inverted rinse bottle so most of the water draining off the sprouts goes down the overflow tube to refill the bowl. If there's room enough to reach in there and wash your hands with the sprout rinse water, so much the better! BTW, the vast majority of folks don't let the water at the sink run long enough to get hot enough to make a difference. It just fills the water line with heated water = wasted heat AND wasted water. This is a great idea: using water which is already being used for one or two other things FIRST.
    See my ible about building your own growing containers from recycled wood here: