Live rock requirements for a new tank

[Canadian]

Just use as much rock as you want to form the aquascape you prefer. There is no good hard and fast rule about pounds per gallon. If anything, those unsubstantiated old rules tend to lead to newer hobbyists filling their tanks with too much LR causing pockets of really poor water flow which is far more detrimental than "not enough" LR. Different types of LR vary in density so, again, pounds per gallon is a bad starting point. Simply plan out the basic shape you want your reef to take and then get whatever pieces of rock you need to make it look the way you want.

But be mindful of enabling flow around and through the rock work.

And by the way, Welcome to Canreef!