Yes the screen size is determined by the amount you will be feeding with the minimum screen being 5x5 inches. I use that size on my reef that isn't fed much and its more than enough. If I didn't have corals in that tank I would probably be doing monthly water changes . If your still planning a 55 gallon a 7-8 inch square screen should be perfect
So I made another quick video today. The emperor is so close to being fully changed. Shouldn't be long now .
Feeding time for chop and crew - YouTube
So I decided to take some pics today .
http://www.flickr.com/photos/95924624@N04/9455311000/
069 by illfixurwhip, on Flickr
http://www.flickr.com/photos/95924624@N04/9455306144/
083 by illfixurwhip, on Flickr
http://www.flickr.com/photos/95924624@N04/9452523699/
094 by illfixurwhip, on Flickr
http://www.flickr.com/photos/95924624@N04/9455302452/
098 by illfixurwhip, on Flickr
http://www.flickr.com/photos/95924624@N04/9452519383/
105 by illfixurwhip, on Flickr
http://www.flickr.com/photos/95924624@N04/9455288872/
131 by illfixurwhip, on Flickr