THIS IS THE END! Need your help!

Hey guys it's been a while.. my reef tank has been let go to say the least. It's a complete mess. Glass covered in coralline, algae everywhere. Which isn't that bad. I've been using a mixture of dechlorinated tap and distilled forever since I couldn't afford an RODI machine and my closest lfs was about an hour away. It's sad to see what I've done to this tank, it was beautiful. I was thinking of a giant water change, deep cleaning etc. however, as I was looking at it today, every single piece of live rock in this tank is covered in aptasia polys. Little baby ones, but still. Well over a hundred in the front portion of the tank alone.. I think it's time to do a clean restart. I have a DSB but now I'm thinking of making it bare bottom since I'm planning to go with tons of corals.. I'm thinking about just killing off the live rock and restarting.. it sucks and will be a pain, but I gotta do what I gotta do..
anyways, I have about 75 pounds of live rock in my 54 gallon corner tank. How much live rock would it take to seed it? I have a pair of clowns, as well as a huge Kenya tree, two beautiful cabbage leathers, and some pulsing xenias that are being overrun by algae. The plan is to move everything into a 60 gallon tub and put their lights over that with a huge filter...