How long should I keep my iphone 5 in rice?

Yesterday night I dropped my phone in a lake for about 1 minute because I was trying to find a net. After getting it out it still turned on, but I left it in a bag of rice for 19 hours. Should I keep it in the rice still if it works fine?

Well, do you don't need your phone that much now?
Just leave it for a couple more hours. #cavemanstyle.

I dropped mine in about 3 years ago. I just left it in rice for 1 day and 1 night to make sure all the water got out of the little parts. After that it was good to use and still works fine to this day.