DWC Hydroponic System Question

by Cody
(Carbondale, CO)

I have been looking to build a NFT hydroponic gardening system, a lot like the one your have on the site here, made with 4 inch PVC and with a constant flow. The only question I have been unable to come up with a good answer for on my own is, how do you "plant" the plants in the system?

I know you put the plants in the holes in the PVC, and I know that the roots must be in the flow of the nutrient solution, and I also know that you must have capillary mat in the bottom of the duct, but how do you keep the plants from washing away into the tube when they are first planted?

Can the plants be placed into net cups filled with clay media? Do they need to be planted into tight fitting styrene foam? Or do they just sit in the water on the mat, and hope for the best?

Thank you very much for your help. Your site is excellent, and I have learned a LOT about hydroponics and what it takes to keep plants alive. I am in the process of building my first system, and I hate to say it, I think I am hooked. There is no end in sight! Thanks again! Cody.

Answer: I remember when I first got hooked. It really is a great (and rewarding) hobby. Plants always need a certain amount of physical support. For seeds and clones, I usually use Rapid Rooter plugs. I used to use round rockwool plugs, but have found over the years that the Rapid Rooter plugs are more trouble free. Once you have seedlings or clones several inches tall (either in Rapid Rooter plugs or in rockwool plugs), it is very easy to transplant them into netted pots filled with expanded clay pellets.

The expanded clay pellets are there only for physical support. It is important that you pre-soak the clay pellets for a minimum of 20 minutes, so they absorb a proper amount of water. Otherwise, they may dry out too soon and damage the delicate roots of fresh transplants. Obviously, your netted pots need to fit nicely into the holes you cut in your hydroponic system.

I believe the hydroponic system you refer to on my site is my most successful system. In this system, I do not use any capillary matting at all. Instead, I keep a high water level inside the tubes, which keeps the roots constantly submerged in nutrient solution.

Instead of netted pots, I made my own from 16 ounce disposable "party cups" using a soldering iron. The fumes from melted plastic are highly toxic, so be sure to do this only in a well ventilated area if you decide to go this route- seriously! Follow the link above- on that page I include some specific directions on how to transplant your Rapid Rooter plugs into the pots full of clay pellets.

Basically, you do not want the roots of your seedlings submerged at first. You add just enough clay pellets (to the netted pots) to let the root ball sit just above the water level, which allow the plants to grow down into the system very quickly. Fill the rest of the cup around the seedlings with clay pellets for physical support. As long as you pre-soaked the clay pellets properly, they should stay moist just long enough to let the new plants grow their roots down into the system. You should never have to water the clay pellets again after that.

There are other ways to support the plants. I have considered making this same hydroponic system with much smaller planting holes....mainly because it is tricky keeping the water level high in the system without causing little leaks out the bigger planting holes here and there. With a small enough netted pot (3/4 inch), I could envision putting a Rapid Rooter plug straight into the netted pot, than straight into the hydroponic system. This would eliminate the need for clay pellets, but I could not say how well it would physically support the plants once they began to grow.

At some point, if your plants grow too large, they may need additional support. For shorter plants, keeping an oscillating fan on them usually makes them strong enough to support themselves. Larger plants can be tied up or supported by a grid of string somehow (tied off to a wooden frame around the perimeter of the garden?).

In all fairness, the homemade system on my website (the one I linked to above) functions more like a deep water culture (DWC) than a nutrient film technique (NFT)- which is why I changed the name of your question. Just remember to keep an air pump or two in the nutrient reservoir whenever you try to grow plants in standing water. I sure hope this helps you out Cody, and Happy Growing!

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Mar 05, 2012
about pumping water NEW
by: George

Hi Jason i just build your nft system and my question is for how long time i have to keep runing the water pump or if i have to let it runs for periors during day or night tanks for your comments George.

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Find out the cheapest and easiest ways to garden productively in this article.

Hi everyone, Jason from Jason's Indoor Guide here. When I got started with hydroponic gardening more than 24 years ago, my first garden used rockwool cubes and B.C. Nutrients....and I remember thinking to myself yeah, sure, there may be a lot of advantages to gardening with hydroponics, for example there are very few pest problems, therefore very little pest control, no weeding, no plowing or tilling the soil, no soil testing or having to add things into the garden soil, no watering the garden....but for someone who just wants to grow their own vegetables and have more control over their food supply and the quality of the food that they eat, the cost of constantly having to buy grow media and hydroponic nutrients makes this an expensive hobby for most people...

Epic Nutrient Change

I suppose when you take into consideration how much money you save NOT having to buy food at the grocery store, it is surely cheaper to grow your own food hydroponically even with the cost of high quality nutrients. Nevertheless, I didn't have a whole lot of money to work with and I needed to make my efforts as affordable and effective as possible....and in the last 24 years I HAVE learned a thing or two!

As you browse through Jason's Indoor Guide, you will notice all of the systems that I use personally are homemade systems. As I got 3 or 4 years of experience under my belt, I quickly adopted a preference to standing water systems and systems that use expanded clay pellets or lava rock, because the media is re-usable and it eliminates a huge operating expense. So once a hydroponic system is built, garden maintenance is minimal- check and adjust the nutrient solution daily, and to change it completely every 2 weeks....and the biggest operating cost is the hydroponic nutrients. (and the electric bill, lol)...

Homemade Cloner

And, regarding the cost of the nutrients....I experimented for about 3 years with making different compost teas and nutrient teas, but there is still a lot of expense $$$ associated with making high quality nutrient teas....like kelp meal, liquid seaweed, rock dust, bat guano, un-Sulfured molasses, worm castings. You can eliminate a lot of this expense by becoming an expert at making high-quality colloidal humus compost, and use your properly made compost as the basis of your hydroponic nutrient solution.

Unfortunately, I have been gardening for over 24 years and I have only just recently mastered this difficult skill....and even then, only because I happened to find a very easy to follow, high quality technique and decided to follow the instructions to the letter. I produced more high quality compost in just one week than I was able to use in a whole year! If you can master the technique, I highly recommend it. It is one of the top 3 things you can do to increase the productivity of your food production efforts, while at the same time decreasing the amount of effort required to grow all of your own food, and decreasing the total cost of operating your food production system.

And when I say decrease operating costs, I mean decrease them to almost ZERO, especially if you are producing your own nutrients...

High Efficiency

The ultimate solution to eliminate the cost of your hydroponic nutrients: Imagine a hydroponic system that does not require you to buy any nutrients, does not require you to make your own compost, and does not require you to brew your own nutrient tea. Seriously! No cost and no effort as far as providing nutrients to your plants! Plus, at the end of the gardening cycle you harvest all of your garden vegetables, PLUS YOU HARVEST FISH from the system--->


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This solution is aquaponics. If you are serious about producing all of your own food and being self-sufficient, this is the ultimate solution for reducing expenses (as much as possible), reducing the total amount of work required, and maximizing the productivity of your gardening efforts. I have been gardening for over 24 years, and it is the perfect food production solution in my opinion.

Produce garnden vegetables AND fish together. Eliminate fertilizer costs!

Besides mastering how to make high quality compost, learning aquaponics is one of the top 3 things you can do to increase your garden productivity, reduce your total costs, and reduce your total work. The product that I learned from is called Aquaponics4you. With all of my hydroponic gardening experience, the first time I came across the Aquaponics4you product I knew immediately that it was something very special! Place an aquaponics system outdoors and use the sun instead of grow lights, and you have reduced every garden expense to nearly ZERO!

The Same System/ 10 Weeks Later!

If you've found this site helpful at all, I would really appreciate it