Hydroponic System Plans

by pH

You would have noticed that my system, in most part, was described over many posts. I don't archive posts so I'll include those posts here. Since the continuity may be somewhat disjointed:-) doing it this way you'll just have to understand it saves me time, copy/cut & paste if you need to. The posts are actually replies to posts or emails in case the wording sounds off.

Just for reference sake I'll call the posts:
HYDRO PLUMBING
TRON 2 HYDRO
[NPK: More information on this setup can be found in NPK's Garden Stories titled 'Multishelf Garden Setup'.]

I'll mention a few things here that I don't think were mentioned in the posts. If you don't see something please do a word search before asking.

The reservoir is 25 gallons. A large heavy duty rubbermaid storage container. It's inside another (I think 40 or 50 gallon) cheaper, lighter weight rubbermaid storage container as a safeguard against spillage and disater:-(. It supplies two growing beds, each on a shelf in the flowrering unit, and two phototrons which I use for mothers. All are ebb/flow using Geolite as the medium. All feed lines going to beds are structurally fastened to each bed using methods described in "Hydro Plumbing" for inserting fittings into planters or tupperware containers, although the posts may give info more tailored to that post at that time.

The flowering unit simply put is 2 shelves. Each shelf is 2x4 feet and has a lip of 1x2 wood screwed around the periphery of its upper surface. Over the shelf and fastened to the lip with staples is a single piece of vinyl flooring with a drain rigged at one corner where a 3" hole was drilled in the shelf. At the 3" hole, a slightly undersized 1/2" hole was cut in the vinyl and a fitting for 1/2" tubing was installed by using a nut and rubber washer on each side of the vinyl, then tightened. Of course the shelves are graded for the drain to be the low spot. These are emergency backup drains in case a bed overflows or a fitting leaks (hasn't happened yet in 3 years). These drains are tied into the overflows for the planters, all are made of 1/2" poly tubing or 1/2" garden hose whichever was most suitable for the run. The drain runs back to the reservoir where the 1/2" discharge handles the overflow for both flowering beds and both trons with the pump delivering 5.1 psi. I would say this is "just about" the limit, any more beds may need the 1/2" drain hoses to feed into a larger discharge line. The planters fill AND drain within 30-45 minutes. Almost forgot, the flowering unit is light tight and has a vinyl shade, I can use the room during the dark cycle this way.

The planters used in the flowering unit are Grossfillex brand (I believe a French co.) I got them because of their size (8"Dx10"Wx37"L), dark gray color, water tightness, and thick vinyl construction. I built 2 simple "U" shaped supports from 1x2 wood to slip over the top to keep them from bowing out when filled with solution. I cover all beds with leftover wrap from rockwool slabs. Slabs users may take this material for granted, just try to find a thin, opaque, plastic sheeting that's black on one side and white on the other, I'm sure it's made, but I couldn't find it locally.

Into each planter I can fit three 3 gallon grow bags filled with enough Geolite to be level with the rim. I usually use two and fill the void left from the other bag with a square gallon jug filled with water and sealed. This displaces solution and allows faster filling and draining of the bed. The feed lines are attached to the planters, and use the same principle for filling and draining as that described in the "Tron 2 Hydro" post. Each planter has 2 feed lines (one at each end). The trons each have one feed line and one 3 gallon grow bag. I use grow bags because they fit the contours of the beds and make it more efficient to fill/drain the beds. They also allow me to remove one without disburbing roots of adjacent plants.

HYDRO PLUMBING

Any "hands on" engineer knows the importance of having a "WELL" stocked assorment of materials to choose from when building anything, especially a prototype. Building ones first hydro system, qualifies as a prototype in my book. Having a "convenient" choice allows one to find the right piece for the job, instead of having to settle for only what's at hand, or making countless trips to the home center or hardware store. I'm also a strong believer in the modular concept, and using "off the shelf" products rather than reinventing the wheel.

As far a hydro plumbing is concerned I believe in using materials that allow me to "easily" change, move, replace, or add any of them at any time. I stay away from anything that requires glueing or otherwise would be considered a "permanent" installation. This allows one to add to their system or modify it without major headaches.

TUBING
I use 3 kinds of tubing, 1/2" for draining, only 1/4" for feeding, all readily found in any garden center. And I always have a supply of each on hand. 1/2" garden hose (can take reasonable bending without kinking) 1/2" block poly tubing (needs elbow fittings or tees to avoid kinking) 1/4" black poly tubing (with 3/16" inside diameter) The poly tubing is commonly found with low volume watering supplies, usually for outdoor underground and/or drip irrigation systems. Some common brand names are Moisture Master or Nelson Rainscapes. Moisture Master 1/4" tubing has a slightly thicker wall than Rainscapes thereby making the ID smaller and much more difficult to fit over some fittings designed for 3/16" ID tubing, I use the Rainscapes 1/4" tubing for that reason.

Any 1/2" plastic garden hose fittings will work with both types of 1/2" tubing. Fittings (elbows, tees, etc) for the 1/2" poly tubing are special but also readily available.

FITTINGS
Where one finds the poly tubing he will also find fittings to be used with it. Make sure you get the tool for punching holes in the 1/2" poly tubing. One of the best aids I've come across is a package of assorted fittings sold under the Gardena brand name with Model #6203. It contains tees, elbows, caps, end plugs, hole plugs, and end caps for 3/16"ID and 1/2" tubing.

One little known advantage of the 1/4" fittings is that they can be used with "any" soft resilient plastic that you can punch a hole in. This includes tupperware containers, and vinyl planter boxes. When the hole is right they will snap-in and self seal, this provides a good anchor where needed. They have to be cut to be removed. I use this technique to anchor 1/4" feed lines to the bed, instead of running the tubing over the top then taping or clamping the tubing.

MANIFOLD FOR THE SUBMERSIBLE PUMP
When one brings home a pump the first chore at hand is how to adapt it to the purpose(s) at hand. Simply feeding the plants is NOT the only purpose, one must also empty and refill the reservoir routinely. Since the manifold is immersed in nutrient solution all the time you must use non-corrosive materials such as plastic or stainless steel.

The outlets of pumps vary in size so the first thing to do is to decide what is needed to get the 1/2" vinyl tubing attached to the outlet to use it as a manifold.

If your pump has a garden hose thread discharge use a garden hose fitting for 1/2" garden hose (make sure it has stainless steel screws). If it has a 1/4" MNPT discharge you may be able to simply slide the 1/2" tubing over the discharge and fasten it with a plactic clamp, or buy and adapter for 1/2" tubing (both are found at any good water pump or pond supply display). Mine has a 1/4" MNPT so I'll descibe my setup below.

To a very short length of 1/2" tubing terminating with a suitable garden hose thread attach a garden hose "Y" adapter that has a shutoff valve on each of the two sides of the "Y". At least one side of the "Y" should also have a snap-on type of connector to match that on the garden hose you will use to fill and drain the reservoir. The other side of the "Y" will be used as the plants nutrient supply. With this "Y" and its valves you will easily be able to shut off the supply of solution to the plants while using the pump to drain the reservoir. Simply snap in the hose, turn two valves, then turn on the pump to empty the reservoir. You can refill the reservoir straight through the pump just by connecting the other end of the hose to your water supply.

For the plant nutrient supply side. Take a length of 1/2" poly tubing, punch holes, and snap-in the connectors for as many 1/4" feed lines as you need. Use an end plug on one end, connect the other end to the vacant side of the "Y" adapter with a garden hose fitting.

TIPS & TECHNIQUES
Use one unbroken 1/4" line to run from the manifold to the plants/bed. Don't be cheap and use sections of left over tubing with joining connectors, you're asking for a leak if you do.

I find any 1/4" tubing gets less flexible with use. The insides also tend to accumulate a coating over time. For these reasons I replace the 1/4" tubing every few crops or so.

If a tube loses some flexibility and wont hug a fitting as tightly as it otherwise could, use a one inch length of tubing with 1/4"ID to slide over the 1/4" OD tube, then slide it over both the small tube AND the connector.

If hoses are difficult to get on the connectors, heat the hose in hot water first to soften it and make it more flexible. A little petrolium jelly can help too.

TRON 2 HYDRO

Buy a plastic rubbermaid bucket. 9 or 11 quart size. Make SURE the bucket is at least 2 inches taller than the tron base is deep. In other words the bucket should stick 2 inches above the base when it is in the base. You'll have to squeeze the bucket to get it between the light tubes when you put it in the unit.

At the top of the bucket, just below the lip, drill a hole and find a way to attach a fitting that either a 1/2" or 5/8" garden hose will fit on to. The hole **MUST** be above the phototron base. This is your overflow outlet, the other end of the garden hose goes into your reservoir. The bucket will fill with solution to this point, the overflow then runs back to the reservoir. Finding the right fitting was the most difficult part of the project for me. I had to use a brass fitting (would prefer plastic) threaded on one side, then found a nut to fit. Put a rubber washer on each side before tightening the nut.

Use an appropriate submersible pump that is impeller driven. Most Little Giant submersible pumps are this type. The important point here is that when the pump shuts off the solution MUST be able to siphon back through the pump. Hook up a length of 1/4" black poly tubing to the pump, you'll have to find an adapter or make a manifold for this. At the end of the tubing going to the bucket attach a small plastic tee. Plactic tees can be found at any aquarium store (or auto supply store under vacuum fittings), and black 1/4" poly tubing at garden centers are know as low volume watering accessories (it must be black).

Place the plastic tee at the lowest point in the bucket (for complete drainage) and fasten it to the side or lip of the bucket so it wont move from the surge of water when the pump turns on. Run it into the bucket at the same place the overflow is located. When solution squirts from the tee it should squirt to the left and right, not up or down. These buckets usually have a slight depression running around the outer wall of the bottom, this depression is ideal for the tee and will act as a sump.

Next you will need something to prevent the medium from resting against the tubing and overflow outlet. Any plastic cylindrical object sliced down the middle, then placed against the inside wall of the bucket will do (even a secion of vinyl raingutter cut in half will do). This allows you to remove the tube and tee if needed, and prevents the medium from covering the orifaces. Since the solution flows in and out, the tee is naturally self cleaning. After a few crops you will want to replace the tube.

I have used both pea gravel and Geolite with this setup and both work fine. I advise using Geolite because it is lighter and provides for more oxygen to the root zone. Fill the bucket with some medium and you're ready to rock n roll.

That's how to turn your phototron into a subirrigation ebb/flow hydro unit. With this setup no solution ever touches the phototron base, and the original integrity of the base is maintained for safety.