What size tank would I need?

[Rocksor]

What kind of pike are you considering? Saxatilis or something from Lugubris family?

 

[Buphy]

I agree with the 180 for the most part though you do seem to have some question marks left. With some smaller fish (not silver dollars)/cutting some "?" You could potentially get away with a 125 but for the differents you might as well go with the 180.

 

[Buphy]

Miss read part of that, my vote is solid 180 minimum.