Reversion back to Archimedes Water Lifters
In the world of engineering, sometimes the change in one design component opens up opportunities to return to earlier designs of other components. Such is the case with the impact of a shallow water tank and the method for lifting the water up to the tray. I had abandoned the Archimedes water lifter approach in favor of the spiral pump because it can be modified to work with deep water tanks such as garbage cans. Once I started making the first actual batch of eight AutoGarden stacks though, the ease of construction and reliability of the Archimedes water lifter (AWL) put it back into the race. A day or two of development and I had the final version of the water lifter concept - a short AWL descending into the water tank and spilling its contents into a drain trough connected to the tray.
The smaller size of the AWL permits the cover to be considerably smaller and unobtrusive. Pictured below is the cover for the AWL and you can see that it is about the same height as the top of the buckets and takes up only 2/3rds of the width of the rack. The remaining space is used as a place to pour water into the tank as needed.
Mosquitoes and water conservation.
This spring has been quite damp and major swarms of mosquitoes are expected when the weather turns warm. In that the standing water of the tanks and trays could serve as a nice environment for the larvae, I am making a major effort to restrict the access of the adult pests to the water. These attempts have the secondary effect of minimizing the water losses through evaporation. To accomplish these goals I have added yet one more layer to the stack. This layer (again made of 1" styrofoam) is a cover for the tray.
The cover has ten large holes cut into it and after the cover is in place, the buckets are dropped through the holes and onto the tray surface below. The holes are beveled in such a way that the weight of the bucket slightly compresses the edge of the tray cover and creates an air tight/mosquito tight seal. Although I haven't had enough warm days to test the theory, it is thought that the evaporation of the soil in the pots and the transpiration of the plants will routinely remove all the water in the tray and provide a further detriment for the mosquito larvae survival.
Coming up... construction photographs and step-by-step construction details
My daughter is home from college for the summer and she is acting as my employee for the new business that I am starting (LookAliveWindowShows.com). Before she starts in earnest with those duties I am having her help me with the documentation. I am an inventor - not a writer. Next blog should include early results of her efforts and some photos of early successes in the AutoGardens. Stay tuned (Do people say that anymore in this digital age?)
Dr Dunc
