ok so ive got a question for anyone that may have a bit of knolage pertaining to gravity fed watering systems. Heres the deal Ive got a resivour that is 2700 litres. Which is about 4 feet tall and 10 feet around. Its 40 higher than the plants up on a hill 50 feet away. Ive got a 5/8 bulkhead to tap into the resivour with a 5/8 battery powered hose bib timer hooked up. Ive got 75 plants. Will a 5/8 garden hose be able to flow enough water down to feed all 75 drip lines. Imagine a " T " if you would up side down. the 75 drip lines will be coming out of the bottom or horizontal part of the "T" and the verticle part of the "T" is coming off the resivour. Will it work??? thanks for your help in advance everyone.
That seems like it will work, you might have to experiment with the set up because of all of the variables, 75 drip lines are a lot so I dunno if you will get the pressure down all of them with only one hose. You might want to have the 75 lines fed by 3-4 hoses, or consider putting a small pump halfway down your line to up the pressure.
This tutorial says a gravity fed system must be 35' higher than than the emitters for reasonable performance. It is based on emitters being a minimum of 18" apart and doesn't specify maximum number of emitters. On my irrigation system I run no more than ten emitters per station, and that's with a (reduced) water pressure of 25psi. 75 emitters on a gravity system sounds extremely optimistic. Don't forget that emitter flow is based on specified psi line flow; i.e. a 1gph emitter will only produce that volume with 25psi of line pressure.
75 plants with a minimum of 4' between them equates to 300' of water feed line from the first plant. I've never tried it, but a gravity feed system based on even 3/4" id hose servicing 300' and 75 emitters without a pump to supply pressure sounds......difficult to comprehend. A 300' line of mature weed plants also sounds like a DEA eradication photo op opportunity.