I have a 125 gallon, 6 foot long tank, with 3 x 250 watt halide Radiums on Coralvue ballasts and an Icecap 660 that pushes 2 x 6 foot and 1 x 4 foot Super Actenic VHO tubes. I started with ARO ballasts, and tried a lot of dofferent bulbs. I after trying 10K and 14K Reeflux, 20K Coralvue, 14K SPS (South Pacific Seas), and 14K XM I finally discovered Radiums. I loved these. My ARO ballasts didn't always light the Radiums on the first try, so I replaced them with Coralvues. I love them. I have never had these ballasts not light or malfunction in any way . I went to 400 watt Radiums on Coralvue ballasts, and noticed a mild increase in light that was not really needed, but a huge increase in heat into the tank, and power consumption. I have a 1/3 horse chiller that was struggling to keep up with the 3 400 watt Radiums and 3 VHO Actenics. I wasted a lot of money trying to find what I wanted, but I couldn't be happier now. Go with 3 times 250 watt Radiums with some actenic suplimentation, and you will be happy.