I'm totally new to hydroponics, and I am just in the process of building my 1st PVC 4" tubing hydroponic setup to try my hand at it.
I have read multiple webpages and ebooks, and watched several youtube videos about the construction and operation of such setups, but after all that I still have some questions about it.
The first question I have is about the actual water level inside the tube and what I am trying to achieve in terms of supplying water to the plants.
Apparently there is a different construction technique between 6" and 4" systems, the 6" system has sprayers inside, while the 4" type that I'm building simply has a tube or single sprayer in one end that flows to a drain in the opposite end.
That much I get, but what I don't yet understand is about how the water interfaces with the plant pot, and how long it is supposed to be exposed to water.
Some instructions I've read state that the overflow tube in the PVC tube should be at the height that allows the water in the tube to just touch the bottom of the pot, thus allowing the water to saturate the growing medium, while others show a small gap between the bottom of the pot, and the top of the water with the roots dangling into the water.
That makes sense, but only "if" you already have a plant with long roots to dangle in the water!
Do I need to start the plants in a different setup first and then transplant them into the PVC system once they have roots, or can I just start them right in the PVC system?
Also, the tube never stays full of water because after the pump shuts off, the water will backflow into the pump, and back into the reservoir below.
This brings me to my next question, at what interval and for how long should the pump flow water into the tube to fill it so the pots get saturated with water?
Should water always be in the tube touching the plant, or is it only supposed to fill the tube periodically to wet the pot and then have the level drop down again to nothing inside the tube?
I'm wondering if the cycle is having water fill the tube and then coming up to the bottom of the pot to saturate the grow medium with water then retreating again (and leave an empty tube), or if there should always be water in the tube touching the grow medium which is periodically replenished with fresh water and nutrients at whatever interval it is supposed to be.
Hope I'm making sense!
I appreciate your help and guidance, once I know the "point" and theory of operation to this setup, I can ensure it's proper design and operation and thus assure my plants will actually survive...lol.