I use fresh sand eels almost exclusively in the rips of Monomoy. I hook them once through both eyes. Fresh eels are the way to go, what you buy at the bait shop will only last one day. Remember these eels the shops sell have been in a baitmans cooler all day and dropped off at the bait store the night before you get em. That makes them two days old before you get em.
' The best way top keep them is on a bed of crushed ice laid out flat in tupperware. Drill holes in the tupperware to let any moisture drain out. TAKE EM OUT OF THE PLASTIC BAG ! The juices ruin them.
I have my customers (charter) cast them into the rips with no problems hooked this way.