For a tank that size acrylic would without doubt be more expensive. Depending on the demintions you are thinking 1/2" acrylic in the minimum tickness to use and that runs about $150 a sheet. Depending again on the application (in wall or other) You might consider the Garf instructions for a plywood tank with acrylic front. I'd like to see whatever you decide!
I wish I had a nickel for every miracle that you easily tricked me into. -Chris Robinson