Ok, so I went with the 2 x 55 watt kit on my 55 gallon tank. It's a lot brighter than the 4 x 40 bulbs I had on there in shop lights. I love the amount of light. So now the next question is do I dare step up to another 2 x 55 kit? Is there anyone running a 4 x 55 watt AH Supply setup on a 55 gallon tank? Semper Fi