i tend to use pre-tied hook lengths and they are between 12 and 20in long but i do
use hook lengths down to 6in sometimes it all depends where im fishing and the water
conditions ect.
If im fishing near snags I use a max of 6inch are you talking braid or mono mono has a higher stretch than braid 8-10in on braid no more than 16in on mono all depends on the water conditions