My Reef Creations may be best known for their beckett skimmers, large calcium reactors and increasingly for industrial and commercial scale protein skimmers, but MRC is a virtual clearinghouse for all custom-crafted acrylic products including these really sweet polypropylene sumps (poly sumps). Most of MRC’s poly sumps are specially built to order for large and jumbo aquarium with all the features you would expect for meeting the special needs of processing massive amounts of water.Â The first section of the poly sumps is usually outfitted with a battery of filter socks, the hobby’s mechanical filtering workhorse. Besides the jumbo size of the sumps, the polypropylene body can be kicked around the room with no ill effects, except for maybe some sore toes. The coup-de-gras of MRC’s poly sumps is the CNC machined openings and lids which greatly reduce noise and salt creep but most of all, they just look fancy with their swirly MRC logos that are guaranteed to never fill up with sodium chloride evaporites. Although we yearn to see some similarly built sumps for smaller aquarium applications, for sump volumes of less than 100 gallons it is much more economical to build the entire sump out of standard cast acrylic. For more information about MRC poly sumps, visit their product webpage and make sure to follow the link for more exclusive pics of these machine crafted beauties.