You can copy and paste the code using the # button.
If you use delay(17); then you won't be able to take any other readings during that time, so instead you could look at examples-->digital-->blink without delay. (it's in your arduino IDE program)
I was thinking that if the ants move really fast then you might only get two positive readings out of 60, which will average out to a low number. There's going to be a little jumpy noise in your readings anyway, your null reading might be between 165-175 so a small reading might average into that and would look like noise.
But I don't know how to look at a series of sensor readings
You can use analogRead for each of the pins and read one after another
Looking at a different temperature logging project might help with coding ideas.