depends on a few different things. lights,type of RW. but ive always had good luck with 2 -3 ,15 min intervals. on botanicare trays with only 2 holes not 4 also running with 2 600 watt hydrofarm air cooled reflectors........try 3 settings of 30 min and if its to much water, work your way down.i would rather have over waterd plants then dead dried out plants
disrupt86 Reviewed by disrupt86 on . How long should my water pumps be turned on for in my hydro system? I am building a small ebb and flow hydroponic system (thats the one where the tub fills completely with water and then empties out). The plants will be put into rockwool, and then into the tub. How many times a day should my pumps be turned on, and for how long should they run for? (my timer can do intervals as small as 1 minute) Rating: 5