My skimmers usually need to be re-adjusted after a water change. Not sure why that is, but it happens almost everytime for me. lol My octopus stays a bit closer to where it should be but still requires tweaking.
I must have seen coralline growth within a few days, it was actually quite startling how it spread. All my rocks are purple now in my 90g and its actually growing on my overflow too. I took a few pictures to try and show you the results so far, flash shows some of the coralline. keep in mind this tank is only about 2 months old and the rocks in the pictures were completely white when they went in.