A fish isn't defined by what he calls with preflop. It's a common misconception. If you raise, and 3 callers come behind you, I might look down at just about anything and call. Then I'll take a chunk out of you with 7Ts, and you'll call me a fish for two hours. Just had odds. Looseness begets looseness. It snowballs. You get a couple loosies at a table, and you'll have a couple of solid players coming in each hand with a wide range just because the fish are +EV shielding them.