I started out with korallias and now run a vortechMP40. My tank is 36x15x16 at 40g and is sandless with mixed species (frag tank). For me, it was worth it. If (when) I get a bigger tank, I'll get another vortech. If you are interested, keep an eye on CL, and the marketplace and FS forums etc. They can be had for as cheap as $300 (not common, but $350 is easy to come across)