I have that fixture over my 75g. I use the 2 54w lights for about 8-10 hours and the 54w for an hour before bed. I have pressurized C02 and algae, but my snails, ottos, and soone Amanos should take care of that. Mine is mounted with the legs. Your photoperiod with the 2 bulbs probably should be more than a couple hours, but it's a quality fixture at a great price with room to upgrade.