Try this link and when you get there click on soldiers on the right and then fill in
last name Nix
union on confederate choose confederate
state or origin choose TX
function choose infantry
hit submit ad see if one of those 10 Nix's are your Nix
Debra
great website by the way for service records for civil war soldiers
soldiers and sailors by the National Park Service
Hoope this helps you.
If you have any problems just answer this and include your email and i will send you a link.