With the size singles you put on they might just become suspending or seriously slow-sinking,it could just be what they look for on a particular day.Going going-
Ya big ones bro and then they are just heavy enough to sink slowly and if they don't sink fast enough you can buy those slimline stick on weights from any tyre balancing place and weight your slider accordingly.
IF you don't come right with the slimline weights good old soldering wire on the hookshanks.
Damn I love artlure - it is all about improvisation