Hashyanswered grow question 4 years ago Go with what organoman said. You can water a lot in one sitting, get plenty off runoff. You want the top inch to dry inbetween watering. Let's say you put 10L through in one watering and then leave it to dry before next you won't get over watering. But let's say you do 1L 10 times during a 24hr period you will get overwatering. Hope that makes some sense. Everytime the top inch dries then water again till you have plenty of runoff.