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 tank...rest 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.