your hydro man is not your friend. whether you go 1 min on 4 min off OR go 4 min on and 0 min off won't make a difference. meaning you don't need a timer.

i recommend using a heat pad under your tub if you feel your reservoir is not warm. you'll notice a significant difference in the amount of time it takes to root with warm water as opposed to cool/cold water. additionally, if your reservoir is warm, the humidity will be higher as well, and you will be able to get away with a 1 hour on, 14 min off cycle, which means u can use a timer from home depot for $10.

i run my pin sprayers 24 hours and it works excellently.