"Canonicus" arrived at the Philadelphia Navy Yard on 25 June 1869 and was decommissioned five days later. The ship was renamed "Scylla" on 15 June 1869, but resumed her former name on 10 August 1869. She was recommissioned on 22 January 1872, and cruised the coastal waters of the Atlantic and Gulf of Mexico whenever she was in commission. "Canonicus" was finally decommissioned in 1877 at Pensacola, Florida. The elderly monitor was towed to Hampton Roads, Virginia, in mid-1907 as an exhibit during the Jamestown Exposition as the last survivor of the Civil War monitors. "Canonicus" was sold for scrap on 19 February 1908.