New build from old acrylic

[Crit21]

I have some acrylic salvaged from a huge old acrylic tank that I cut apart into more manageable sized panels. Since it was previously used, I plan to prep any surface that isn't freshly cut before bonding. I think maybe super fine sandpaper followed by some sort of non-reactive solvent (i.e., won't melt the acrylic) ought to be the right way to remove any type of residue, but the question is which solvent to use? Does anyone have experience in this?

 

[Crit21]

This is the "before" pic of the tank I cut apart. It was too big to move in one piece, and was too big for the thickness (or lack of) of the 14 1/2 foot long tank. I'm cutting it up into pieces to make an 8 foot tank and sumps.

 

[Crit21]

Disassembly in progress.

 

[Crit21]

Repeat post. Sorry.