I just completely redid a clear for life 90. I bought the three step package from Novus. The tank is 48x18x24 and I did the inside and the outside and I have about 1/3 of the bottles left.
A couple tips: unless you have significant heavy scratching there is no need to use 500 grit paper. If you are going to use 1000 grit paper on a random orbit sander make sure the tank is clean and free of ANY DEBRIS. It will get caught in the paper and just annihilate the acrylic and you will have to really start over. Just for reference, fine aquarium sand is approximately 80 grit sand paper sand. You don't want to drag that around on the acrylic. Use only wet sand paper and it should be wet enough that the sanding debris doesn't form a paste. Clean the tank thoroughly when you step up to 2000 grit then the same thing, keep it wet enough it doesn't form a paste. I just had a squirter bottle and I would periodically spray the area I was sanding. I wouldn't try to do more than 2'x2' at a time.
When your done sanding the tang should be uniformly foggy. Get a good corded variable speed drill, put the polish on the pad not on the tank and start a slower speed so you aren't blasting the polish all over the place. Keep the whole thing moving, don't let it get too hot. When you've done the whole tank with the #3 polish was the tank thoroughly to get all of the polish off. Same process with the #2. Buy yourself a box of good microfiber towels and change them out often.
If your patient this stuff is nothing short of magic. Take your time, don't get to aggressive. Show us some pics along the way. It's totally worth it in the end.
