Acrylic buffing
 

What is the best way to buff out scratches on an acrylic tank? Tank size 180 gallon.

Wet sand the scratches with 1500 to remove them, then use a high-speed buffer with clearcoat safe buffing compound followed by clearcoat safe polishing compound. Essentially you are treating it like automotive paint.

Thank you so much. This is going to be my dream tank so I want it to look the best possible.

How do you do the inside of the tank??

Mines one year old and the scratches from scrapping the algae on the inside are out of control. Every cleaning equals more scratches.

Here you go. I did a step by step tutorial complete with pictures and videos on removing scratches from the inside of my fully stocked reef.
http://www.reefcentral.com/forums/sh....php?t=2538092

That said, you need to be more careful with your cleaning. There is no reason to be scratching the tank like that if you are careful around the sand bed. Maybe get a good magnet scubber and use a sleeve over the cleaning pad and be careful around the sand bed. This is the sleeve I am talking about.
http://mightymagnets.com/algaeCutterBag.html

I cut old filter sock material the size of the inside mag pad. It sticks easily and is easy to remove and clean. Cost nothing, no scratches and does a job on glass or acrylic tanks.

I filet Mr Clean Magic Eraser pads and put between the inside mag float.