mariobrothersleeve
squirrel
Why?You can make a overflow out of pvc that would cost less then 20$. Go to youtube and type in DIY overflow PVC. Much easier then buy a box or drilling a tank. It's what I'm going to do when I set up my sump/refug.
For 55 bucks, youll have an overflow box and not have to cut and glue and keep a constant prime. Drilling a tank is the best option, but tempered glass is the issue. Drilling is the easiest because there is very little risk on overflowing and up keep. This is from experience, not from a google head