I bought one for a 38 gallon with a 65 g skimmer and a 500 g circulation pump. I think that 206 is only rated for a 45. I'm a total noob but it seems low to me.
Yeah I agree, to small...I read that it was only rated for a 40 gallon... He told me he found a good protein skimmer but he hasn't told me the name yet...it has to be very good to make up for the lack of filtration in the filter
I have a 205 running on a 20 gallon xtra high with a large pc of driftwood that disrupts flow, and I have some slow/dead flow areas here and there so I would have to say definitely too low flowing for a 55