i am using a NFT hydro system and was wondering if i should leave the res pump on all the time or put the pump on a timer and say leave the pump on for 20 minutes and then switch it off for 40 minutes then back on for 20 minutes then off for 40 minutes and so on and so on which is how i've got it at the moment or is it best to put the pump on a different time schedule as im not shore and would appreciare any help, thank you!!!!! 
)
)
