I tested the single module....not the 600. one! The single fiture is 99. Two would be good for a 48" tank....4 for longer....I am keeping fish not plats or coral but the intensity would be great for plants.Myarbro;4771183;4771183 said:I would not be caught dead paying over $500 for a fixture like that. Sure, it might look nice, but it's really meant for sw corals. You don't need something that intense for freshwater.