i am leaning towards going with a sump over a wet dry simply for the room. in another post i was asking about a DSB for a 55 and it was suggested not to go that route for lack of surface area. i want to decide by tomorrow so i can take advantage of the sales. For some reason the pro flex is quite a bit more then the rest is there a reason for it ? i like the idea of having the socks but if you use carbon and GFO don't they require a canister with a pump to force the water thru ? i don't know what else you could put in the socks. But if i go with the wet dry then all i would need room for is the skimmer. What do you guys use and why ?