Okay I've managed to narrow down my list to these filters now I just need help choosing one. Price isn't the problem I need to know which is the best for biological, mechanical I suppose chemical isn't as important. This is for a 55 gallon tank. I'm not sure if my LFS has the Ecco or Classic Eheim. I choose these because I've heard good things and my LFS has them and the prices are pretty close to online.
Eheim Professional II Model 2026 = $159.99 US
Eheim Professional Wet/Dry 2227 = $179.99 US
Eheim Ecco 2236 = $94.99 US
Rena FilStar XP2 = $79.99 US
Eheim Professional II Model 2026 = $159.99 US
Eheim Professional Wet/Dry 2227 = $179.99 US
Eheim Ecco 2236 = $94.99 US
Rena FilStar XP2 = $79.99 US