zonkers/minkies are probably amongst the best out there, and pretty easy to tie, nothing too complicated about them. if you're fishing for fish taking perch fry, use an olive version with orange at the head. Something like this:

for fish taking roach fry use a grey/white version with red at the head, so simply go for a matching colour with a bright hotspot.
use them on any line, depending on how deep the fish are, just use a slow retrieve with twitches.
also, as a personal preference, I wouldn't use a longshank hook, they bend out too easily with the big fish around at that time, use a standard shank heavyweight (B175 or comp. heavy), alot stronger and also you can use a longer tail to get the right length, which will give you more movement.
hope this helps.
cheers,
john