Believe it or not, the famous infinity pool photo is actually captured from the local caravan park pool... So whether you stay the night or just pay for day pass, you'll get the shot. I'd recommend going first thing in the morning or at sunset, for the best lighting and less crowds.
The bar at the caravan park is also a big vibe, so if you're staying the night be sure to go get a bev.
I also did the sunset cruise while I visited, and it was actually so worthwhile and really good value! The sunset from the water was SO special, so if you're around for 2 nights, I'd recommend watching a sunset from the pool, and a sunset from the cruise.
You can also do a short walk down to the river, where my friends and I went for a dip off the pontoon.