I am limited in height in my 5ft grow tent, so I would like to know if a drip system will work fine if the water is returned by gravity to the bottom of the reservoir instead of top (it will contain about 1.5 gallon). I would save me a couple of inches as the plants would be lower. Also, any tip on how to avoid roots to block this pipe ? I plan to use 5/8in for all tubing of the system.