I have an ASM G4XX - 30" tall, with Sedra 5000 needle wheel. This thing is big! The chamber diameter itself is 8.5". The smaller G4 model [24" tall] with the Sedra 5000 is rated at up to 350 gallon. It was given a vinegar bath and is clean and ready to go, no cracks, and in pretty good shape. These skimmers go for upwards of $430 new. Yours for $175.Attachment 40994Attachment 40995Attachment 40996