This concept has intrigued me for quite some time. My version uses a 5gal bucket, quartered vertically. Siliconed one peice into the corner of the 75gal. So, I have a pie shaped "overflow" box in the back-corner of the tank. Filled it with plastic mesh and scrubbies. Put a powerhead in the bottom w/Tygon tubing attached to form the return line OUT of the 'box'.A little tricky to balance the flow, but did an awesome job!!Worked great until I did a large waterchange and the weight of the water inside the filter pushed apart the seam at the top. The rest of the seal wasn't far behind. In the end, I stuck the p-h on a large sponge filter. Will attempt again on the 280 plywood project.
75g Afra, Ceruleaus, Trewevasse, Acei
55g Tropheus 'Ikola' colony
40tall Cyn. Afra colony
30tall Elongotus colony