I got two Diablo's, the XS225 and the XS250. These replaced two undersized protein skimmers in my 200 and 250 gal. reef aquariums. They're quiet and produce an amazing amount of micro-bubbles. I'm extremely pleased with the amount of skim-mate waste they pull out. The collection cup is easy to clean out and empty out. The XS250 has a large footprint, therefore make sure you measure your sump for accommodation. The XS225 Sump Space Saver is perfect for my 200 gallon sump.