Location of Airstones
in the Hydroponic System

by Bob
(Fish and Jacks, Canada)

Hey Jason, Thanks for the great website! I was reading over your page "My Most Successful Homemade Hydroponic System" and noticed in the drawing that it appears the aquarium pumps and air stones are inserted at the elbows. In the text you did not mention the location of the air stones.

I was wondering, if I had three air pumps and 6 air stones in the reservoir, would that do the trick? I elected to go a bit bigger with the design and went with 20 feet of 4 inch by 4 rows as in the drawing, giving me 96 plant holes.

Answer: Bob- when I originally designed my most successful homemade hydroponic system, my concern was that the oxygen in the nutrient solution would be depleted as the solution flowed through the roots of more and more plants. I will be the first to admit my knowledge is limited, but this concern came from what I know about how oxygen affects plant growth.

If this assumption is correct, it made sense to me to space air stones throughout the hydroponic system to replenish the dissolved oxygen levels every few plants....this way the plants farther along in the system would not suffer for lack of oxygen.

To what degree my assumption is correct is debatable. On one hand, the rate of flow through this system is so quick that the plants may not have time to sufficiently deplete the dissolved oxygen before the nutrient solution is recycled through the nutrient reservoir. I believe this is probably the case with this system design.

On the other hand, most plants prefer a well drained root zone with a lot of air....having air stones every few plants could be the difference between having good results or bad results, especially if the plants are surviving close to the limits of their natural abilities in that environment. Also, as the number of plants in the hydroponic system increase, the chances of my assumption being correct also increase (which would be the case with your larger system design).

The air stones in my design are, indeed, installed in the elbows of the system. I made a 1/4 inch hole with a drill and inserted the air tube, then slid the air stone into place in the elbow and attached it to the air line. I found this strategy has one additional benefit... if your air stones are in the nutrient reservoir, they will be in the way when you go to do the nutrient change every two weeks.

Hopefully you have read my tip on using two nutrient reservoirs (one full of plain water waiting for the next nutrient change), which definitely makes life easier. It also eliminates the possibility of root damage from temperature shock. Also important to success is how to maintain the nutrient reservoir.

One more thing I must address before I let you go....hydroponic systems longer than 8 feet (of this design) have a tendency to sag in the middle. This is due to the weight of the water, and also because the plant holes weaken the structure of the PVC pipe. Even in my first 8 foot system I had a small issue with sagging because I had not provided any support in the center of the system. Therefor, my recommendation to you is to provide solid support points for the pipes every 4 feet.

I certainly hope my rambling ideas on this matter have helped. Once you are up and running, I would love to hear more about your final system design and what kind of results you are getting. Until than, Happy Growing!

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AffordableGarden Design&Setup

(10 week update below)

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...

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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