Cisak made his Pompey debut in the 1-1 draw at Coventry on Saturday.
With his place between the sticks now secured, the 23-year-old wants to impress the Fratton Park faithful during his short stay on the south coast.
Cisak told The News: "Portsmouth have a good history of goalkeepers so, obviously, I want to make sure I'm one of those great keepers as well, even if it's only for a month.
"Anything is possible. The aim is to do really well here, but I'll take it one step at a time."
He added: "The fans are great. It's not something you get nervous about. It's something you get buzzing for."