It depends on the strain and the grow medium you are using.

With grow rocks or lava rocks in that type of setup you can run a drip 24/7. If you are using Rockwool then you need to cycle the water or the root ball can get soaked and overwatered.

Not all strains can take 24/7 drip and some can. That is another factor to consider.
Zandor Reviewed by Zandor on . How long to run drip system I have a homebuilt drip system. It consists of a large rubbermade with holes cut in the lid for 8 net pots. There is a submerged fountain pump inside the rubbermade that pumps up to each of the pots. How long should I run this mother? Right now it is runnning for 15 minutes every hour. Keep in mind that I am limited to only 15+ minute intervals as thats all my timer allows. Right now the plants are pretty small. Rating: 5