Lee's Specimen Container Convalescent Home In Small Has A One Inch Hanger To Fit Most Aquariums. Hang this cup on the side of your fish tank when you want to isolate fish for medication, to see if they are sick, to transfer them to other tanks. Can be hung inside the tank to take advantage of the heat. 5 1/8" Long x 2 1/2" Wide x 4 1/2" Deep.