Currently on my 210G I am running two emperor 400s, a topfin 60, and a tetra something that is rated for up to 60 gallons. I am wanting to improve the filtration and was planning on getting two more emperor 400s but found that there is not enough space due to the center brace. So now I am looking for another alternative to replace the topfin and tetra filters. I am also willing to replace all four filters if it will improve the flow. Does anyone have any input that may help me out?