Initial photo (time = 0). Line indicates liquid level
Home > Semi-Hydroponic Culture > Inert Media Comparison > Early Experiments > Buoyancy > Absorption & Packing > Capillarity
While the ability of a medium to store water and nutrients is important, even more critical is its ability to deliver it to the plant and to the surrounding media. That is why we must assess the capillarity of the media.
This test utilized the same 300 ml plastic containers as before, and due to the poor performance of the TWFKI material, it was dropped from consideration and not tested. The other materials were subjected to the following procedure:
1. 60 ml (20% by volume) water was added to each container.
2. Sufficient medium was added to fill the container.
3. Depth of the water, and height of its "climb" in the media was photographed immediately, fifteen minutes later, and again 24 hours after the insertion of the medium into the liquid.
Initial photo (time = 0). Line indicates liquid
level
Second photo (time = 15 minutes).
Lines indicate level water has risen by capillary action
(Aliflor = 0, PrimeAgraTM = 1/2")
Final photo (time = 24 hours).
Arrows indicate liquid level.
After standing undisturbed for 24 hours, the liquid level in the Aliflor is essentially unchanged, and capillary action has carried moisture to material about 3/4". The liquid in the PrimeAgraTM sample, on the other hand, has dropped about 40% from its original level, and has transported the liquid into the remaining medium, which is totally wet, clear to the top.
A warming of ambient conditions compared to the initial testing caused some fogging in the container of Stalite (and poor photographs), but 24 hours after the test was begun, the water level was essentially unchanged, as only about 1/2 inch of the material above had be moistened through capillary action.
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