Most sea fisherman use bait elastic to secure their deadbaits on.
Works a treat.
Check out the other bait holding products.
Bait Elastic..... great for cost effective way of holding bait onto trebles. Just wrap around and pull. Will keep bait on all the time.
Rig Wire.....Great for the really soft baits like Sardines / Herrings etc. Will keep bait on all the time
PVA Cable Ties....Fantastic for keeping the bait on during the cast. Even when drifting.
Melt time obviously depends on water temp, but once in contact with water they start to melt and will pull freely on the strike. Almost used like the old instant strike rig.