Setting lobster pots

A lobster fisherman once told me that he used salted baits for his pots because fresh bait attracts congers and doggies.

I got me some lobster pots now and caught a few nice brown and spider crabs already, but I also get tons of dogfish in these pots, even really big ones which I do not enjoy to handle in these small pots at all..
Is mackerel the wrong bait? I use 2-3 of them chopped in half, never leave the pots out longer than a day of fishing.

Where are you based?

Based in Galway, but fishing in a big area, from clare up to mayo.

I've often supplied a leisure potter with a few Ballan Wrasse they seem to work well for him.