Aquarium filter arrangement including pre-filter member and methods

An aquarium filter assembly comprising:

• (a) a housing including a top, a bottom, and an outer sidewall extending generally vertical therebetween and having an interior;
• (b) a transfer tube within the housing interior to convey aquarium liquid having a distal end;
• (c) a pre-filter member within the housing interior secured to the distal end of the transfer tube;
• the distal end being vertically above the pre-filter member;
• (i) the pre-filter member containing filter media and allowing filtering flow from inside of the pre-filter member to outside of the pre-filter member and into a pre-filter chamber;
• (ii) the pre-filter chamber being positioned to surround the pre-filter member to result in liquid within the pre-filter chamber to be turbulent, causing contact with the filter media within the pre-filter member;
• (d) a mechanical filter chamber downstream of the pre-filter member;
• and
• (e) an internal wall within the housing interior separating the transfer tube and pre-filter member from the mechanical filter chamber;
• (i) a gap being between the outer sidewall of the housing and the internal wall and being an open volume to allow liquid to flow from the pre-filter chamber into the mechanical filter chamber.