Be Confident with ESHOPPS ALPHA-CLASS, ALPHA-FUGE Refugium designed for the Advanced Hobbyist incorporating ESHOPPS unique Triple Water Channel Design and an easy access Filter Sock w/ a clear removable lid. The ALPHA-FUGE Refugium Sump features a Large Protein Skimmer compartment with Dosing Tubes and a Probe Holder Cradle. In addition, a large Return Pump compartment with built in water level ATO Float Valve and a Hang on Multi-Purpose Media Tray. The Multi-Purpose Media Tray can be used as a in sump passive media filter. Additionally, the Refugium compartment has a removable ALGAE-BLOCKER panel along with a built in Bubble Trap with easy change Mini Filter Sponge. Be Confident that the ALPHA-FUGE Refugium Sump will meet all the demands an Advanced Hobbyist can dream of.