Looked in the CWPI (Civil War Pension Index), listing of vets or dependents who entered federal pension system from 1861-1934, and no record of John Kanuth. You could get copy of his military file from the National Archives. However, it usually dosen't contain much information.
John Kanuth, in 1910 census shows wife as Nellie. In 1918 draft record wife listed as Nellie Pearl. In 1930 census wife listed as Bertha (five years older than Kanuth), three children, Frederick, age 22, John G. age 20 and Robert C. age 17, living in Columbus Ohio in 1930.