I'm using 18 gallon totes with a 27 gallon reservoir. I have a 250 gph water pump for the return line and a 58 watt, pressure 0.028 MPa , output 0.075m3/minute air pump . I also have a 20w , pressure >0.02 MPa ,output 45L/min air pump. I have a 1/4 HP water chiller but I want to help a friend and set a system up for him minus the chiller if I can without causing root rot?