150' of line on my box anchor. Do not put chain on your line if you use a box anchor. One of the main purposes of chain on a Danforth-style anchor is to keep the line low so it pulls the anchor flat, not up, making it set better. A box anchor is desigened for the line to pull up at about a 45 degree angle, so use no chain.
~100 foot of line on both Box Anchors with loops at 50, 75, 100 feet for the clasp that hooks to the bow eye. Unlike Mike I actually have a floating ball for the anchor line!
You don't need an anchor for beaching at Moabi,
25' box with a slide for the back on my STOKER on the river. Always facing out!