Shiny Krabby rate?

So ive completed 13 shiny krabby quests and no shinies. I'm just now really trying to get a shiny ANYTHING by completing quests. Does anyone know how many of these i gotta complete before i finally see an awesome shiny staring back at me? I wish Niantic would increase chances of finding shinies. i know the fact they are rare make them more valuable but i think they could make it a little easier. ive only caught one shiny in the wild outside of community days