A "pool of water" on a farm or ranch . . .

My wife and I have had a two-decade discussion about whether the proper Texan term for a “pool of water” on a farm or ranch is a “pond” (as she has argued) or a “tank” (my argument). 

This evening I ran across the 1962 book by E. Bagby Atwood, *The Regional Vocabulary of Texas,* and it answers the question! While “pond” is prevalent in Louisiana, Arkansas, and northern Oklahoma, plus a small minority usage in East Texas, in Texas generally, “tank” predominates....at least as of 1962.....