Hmmm, the Box device has a 10'x10" wick surface area, about equal to the surface area of five 4" pipe wicks or seven 3" wicks, the tub and bucket has a wick surface that is many times that, you do understand that the tub is the wick in the Tub and Bucket right? The bucket is not a wick.You nailed it BC, hauling tubs around was just a little too iffy in my situation. Other than that small modicum of security, you gain nothing and lose water capacity and wick surface for about the same amount of work to get it installed. I'm not entirely convinced that the single, smallish wick will be adequate either.
Nope, nope! How are you going to keep burrowing animals like Gophers and Moles from digging holes through the bags? Thats why I used the Tub!Then it occurs to me that the tub and bucket principle could be accomplished by using plastic garbage bags doubled up instead of the tub (think the big yard sized bags for leaves and such rolled down to the top of the bucket.
http://www.physicalgeography.net/fundamentals/8l.html said:Soil Water Storage
Within the soil system, the storage of water is influenced by several different forces. The strongest force is the molecular force of elements and compounds found on the surface of soil minerals. The water retained by this force is called hygroscopic water and it consists of the water held within 0.0002 millimeters of the surface of soil particles. The maximum limit of this water around a soil particle is known as the hygroscopic coefficient. Hygroscopic water is essentially non-mobile and can only be removed from the soil through heating. Matric force holds soil water from 0.0002 to 0.06 millimeters from the surface of soil particles. This force is due to two processes: soil particle surface molecular attraction (adhesion and absorption) to water and the cohesion that water molecules have to each other. This force declines in strength with distance from the soil particle. The force becomes nonexistent past 0.06 millimeters. Capillary action moves this water from areas where the matric force is low to areas where it is high. Because this water is primarily moved by capillary action, scientists commonly refer to it as capillary water. Plants can use most of this water by way of capillary action until the soil wilting point is reached. Water in excess of capillary and hygroscopic water is called gravitational water. Gravitational water is found beyond 0.06 millimeters from the surface of soil particles and it moves freely under the effect of gravity. When gravitational water has drained away the amount of water that remains is called the soil's field capacity.
Figure 8l-1 describes the relationship between the thickness of water film around soil particles and the strength of the force that holds this water. Force is measured in units called bars. One bar is equal to a 1000 millibars. The graph also displays the location of hygroscopic water, the hygroscopic coefficient, the wilting point, capillary water, field capacity, and gravitational water along this line.
Nice find there Lt.Herb!
Some1here- I'm not sure how to judge the capillary potential of rope wicks, I'm sure they can work, but how far they can move water, and number needed is unknown.
One reason I moved away from rope wicks in my design was seeing how well soil wicks work(via the Earthbox), I also like the fact that the roots of the plant can grow into the soil wicks and establish direct contact with the reservoir, impossible in rope wicks.
My advice to you would be to use many wicks, like dozens, and don't expect the wicks to transfer water very high.