I find that players are either bad leaky, or tight, stealy at these levels
semi bluffs are reasonably effective the times you don't have a hand, assuming your hand range and position is solid.
Focus more on your table image per individual table and the players style as these are the two factors that will give you the right insight,
things like are they limping do they utilise a optimal 3-betting strategy
There are times on awful tables they'l just limp 80% or more of the time, depending on which sites of course