Slowly making some progress on the 180! Picked up a gallon of muriatic acid over the weekend and diluted it into 3 gallons of water. Cleaned the front and both sides of the tank beautifully letting each side soak for about 1 hr per side. Didn't bother with the back or bottom since it will hopefully be covered in coralline eventually anyways. Next step will be buffing the front and sides to remove any scratches.