REF#: AIO132 - All-In-One Rimless Show Tank (7 sizes available)No sump necessary!!! This tank has a built in filtration system located on the back of the tank Made with 3 4" thick Cell Cast acrylic Drain slots on each end of the tank for optimal water skimming 4 sections in the back for the filtration system (Drain Skimmer, Fuge, Return and Carbon Media Section) Maximum skimmer footprint for tank sizes 30"(L) and 36"(L) is 4. 25"x6" Maximum skimmer footprint for tank sizes 40"(L) and 48"(L) is 4. 25"x9" Tank