If you’re looking to build a reef tank and want to cram as much filtration into your system as possible, you may have to think outside the box and install a sump in a closet, crawlspace, basement, or garage. These remote setups are often located in areas where there is far more real estate, offering up a place for huge sumps and protein skimmers, as well as other really important items. Garage sumps are fairly common, but they might require you to insulate the garage or partition off a small room for the equipment. Basement sumps are great because they offer up a ton of space, but they require huge pumps to move water upstairs to the display tank. Crawlspace sumps are a bit more difficult, as the space they offer may be plentiful, but not so much vertically. Closet based sumps can work great, especially if they share a wall with the aquarium. But, the drawback here is that you either lose a closet, or your stuff in the closet gets salty and wet from time to time. Each of these setups has its pros and cons, and obviously not every house will be able to accommodate all of these options, so pick the one that works best for you and run with it (assuming you need something more than what will fit within your aquarium stand).