During the temperate season the carp here are very mobile. They mostly cruise fast in pods of 4-8 at mid-depth. In spring they can be aggressive! now they are mostly resting and feeding on the bottom - very skittish. They don't seem to associate themselves with any structures or specific territories but will cruise breakwalls and rocky structures on a fairly regular basis. Perch here (yellow perch) are more inclined to hang around wrecks, breakwalls, weeds and any place they can find food and shelter. I mostly dive out in the open or along a breakwall here. Perch are known to prefer weedbeds and their markings are designed for that kind of environment. I mostly see young ones along the breakwall - in winter they move out deeper but I haven't encountered them yet.
Short answer is; Rock breakwalls are good
In terms of approaching. I'm mostly photographing these species so I need to get really close. In my experience it is very rare than any fish will let you approach it - I normally try to get into their area, dive in a non-threatening way (never toward them!) then wait for them to come it. For spearfishing you can line up and put on a surge to get close for the shot but with photography I need them to come in closer than spear range.
