i went in the morning before work. around 10:30. i got the other powerhead on its way. im gonna plug both the returns and powerheads into the wavemaker. alternating opposite sides. aka. left return on while powerhead on right is on. and right return while left powerhead is on. to create as much alternating movement as possible. i was reading up and i might have too much rock also. they say it creates lots of nitrates and hard to keep things thriving with too much rock causing algae. interesting ****.