What are the top T5 HO fixtures currently

[phi delt reefer]

depends on the fixtures. Like the ATI ones do produce more light than the standard teks but it may not be that obvious (Difference is only 15 to 20%). I have also heard that some bulbs looks slightly different on different ballasts due to the variance in actual output voltages.

some things to consider before going with TWO 3 foot fixtures....

(lets assume you need 6 bulbs front to back)

1. 12 36" bulbs cost more than 6 60" bulbs

2. T5HO bulbs have a cold "no light" section on the tips of the bulbs. Add to that the room needed for the endcap and casing for both lights. This means the centre of your tank will have a dim area. May not be too noticeable. I think Grizz said he was running two fixtures over his tank so it would be best to consult with him as to whether that gap is visible.