Lessons Learned

The hydroponics equipment was assembled and set up as described in it's accompanyingliterature. There were, however, a few things that should have been common sense thatweren't mentioned and where we made mistakes. This page will be frequently updated as welearn from experience and from the many experiments to be conducted under this project.

• Our first mistake was particularly bad, as we set the nutrient level at maximum, per the instructions. For small seed this is proper; however, for some of the larger seed which needed to be planted deeper they ended up IN the nutrient solution. In addition, many of the smaller seed were planted too deep and were also submersed in the nutrient solution. None of these seed survived.
  • The pots should be filled to the very top with the gravel-like material
  • Seed should be covered; but must NOT be, even partially in the nutrient solution. The gravel does stay wet below and seed germinate must faster than in soil.
  • Seed planted within an individual growing chamber should be of about the same physical size. For large seed the nutrient level should be lowered somewhat to allow the seed to be completely covered with the gravel, yet NOT be in direct contact with the surface of the nutrient solution.
• Our second Major mistake was not taking into account the number of days-to-harvest when planting seed in any particular growing chamber, as what was planted within a particular chamber was rather random as can be seen under Cycle 1 Plants . This eventually resulted in having to re-group plants in different growing chambers. This was because the plants germinated and grew roots at different rates within a single growing chamber. Once the roots exit the pot and are mostly down in the growing chamber nutrient solution, the level within the chamber of the solution must be lowered so that at least an inch of the root system below the pot is above the solution level, in order to obtain oxygen for the roots. It is therefore most important to group plants within a chamber that have about the same root growth rate.
• After planting the seed, don't wait until they germinate to turn on the lights, but turn them on immediately. This results in two things. The light heats up the surface of the growing chambers, which in turn heats the nutrient solution. We found that within 24 hours the nutrient solution in the large system was heated from the low 60's F to the lower to mid 70's. This temperature is ideal for germination. Second, we found that a strong light source above the pot made it easy for the sprouts to orientated themselves, sending roots down and leafy growth up. We had also found this to be true when planting seed indoors in peat pots for later replanting in the outside garden.
• Another most important lesson learned relates to the size of a particular hydroponics system. Shortly I will complete the section on Nutrients for seed Germination and Initial Growth. When this section is completed you will find that there are three distinct phases of plant growth which require different nutrient mixes. They are the Seedling Phase, Vegetative Growth Phase, and Blooming and Fruiting Phase. When using a Large system the entire system can only be setup for a single nutrient mix. When growing plants with a wide range of timing between their individual growth phases this causes a real dilemma for the grower. "When do I change the nutrient solution to the next phase", as some plants are blooming while others are far from blooming; not to mention the pots where something goes wrong and nothing sprouts and you have a nutrient solution for the vegetative phase (which is MUCH to strong) for seedlings and would kill them. Therefore, at the current time most of the large system has empty pots due to this difference in timing.

  A large system should only be used for "production", that is, for growing a lot of the same thing as would be the case post PS, and you have many individual large systems. As we are actually experimenting with small numbers of many different plants, we would have been much better off purchasing several of the small two growing chamber systems than purchasing a large system.

• After working with both the large and small systems and seeing their construction and how they work, once the aquaculture system is up and running I plan to construct several small one or two growing chamber systems so that the nutrients can be changed at the appropriate times for the particular plants in the single small system. The design will be extremely simple to build and extremely inexpensive; the highest cost item being the pump for circulating the nutrient solution within the growing chamber(s). As this pump is small and the demands on it low, so is it's relative cost. The specifics on this system will be added to this site as I construct one of these designs.
• One thing that was not anticipated is how LARGE the plants would grow.  We setup the large system with the growing chambers spaced close together in order to save space in the basement for other systems.  The system could have been set up with every other growing chamber facing one direction and the other chambers facing the opposite, both radiating from the center reservoir.
• Of MOST importance is to check the level of nutrient solution in the reservoir EACH DAY, as the plants transpire very heavily.  The volume of solution must be "topped off" whenever it drops.  In addition, a TDS (Total Dissolved Solids) and pH meters are a MUST.  TDS and pH should be checked every day.  As the plants grow they use nutrients and several factors affect pH.  These must be adjusted to keep them within acceptable limits.  pH should be between 6.5 and 7.0, while TDS should be between 1300 and 1600.
• Many plants, such as tomatoes, will grow from cuttings.  A complete 10 pot chamber in the small system was populated from cuttings from the other chamber planted from seed.   ALL of these cuttings have lived and after a week are showing roots exiting the pots.  These "plants from cuttings" make it possible to keep a crop going without it ever having to start from seed.
• It is most important to insure that plants are spaced adequately and plants which grow tall aren't grown with short plants.  The tall pole green beans shielded many low growing plants, virtually killing them due to shading them from light.  Other plants had large wide leaves which equally effected their neighbors.
• We were unable to get many plants, such as lettuce and leafy vegetables to go-to-seed, even after several weeks of blooming and fruiting nutrient solution.

This page was produced by Ron Darby.