What I have. One $15 fan running a couple hours a day keeps my tank cool no problems even on hot days.You could have almost certainly used lower wattage MH, then. I remember people dropping big cash on that Solaris when it came out and it ended up dying a quick death when multi-color stuff came out - don't remember it doing all that much better than "just fine." Don't recall people saying that it was an awesome light, or anything. Time does fly.
150w HQI might have been your jam... way less heat too.