Hi Don, Not a lot for the 29. It come to 1.89 WPG. Been my experience that get lot more bang per wattage with PCF than NO flo. The 29 was running on about with about he same wattage of regular flo and grew mostly Java fern so expect it will improve performance. I miss typed on first email. The double 55 watts units sits over couple side by side 15 gal tanks so each tank will have 3.78 WPG. These are my high light grow out tanks and with the CO2, which is run high since no fish in those tanks and lots of nutrients, things really go or I should say grow. June > How many "WPG's" will you now be running in each of those tanks? > -Don > ------------------ To unsubscribe from this list, please send mail to majordomo@thekrib.com with "Unsubscribe gsas-member" in the body of the message. Archives of this list can be found at http://lists.thekrib.com/gsas-member/