Hob skimmer algae?

I have one hob skimmer that faces a window, and it seems to be growing coralline should I be concerned?

 

It could become an issue, if it builds up to much and affects performance
also activity in there, such as when you lift the cup to clean it, could cause particles to flake off and they may find themselves stuck in the pump impeller

Steve

 

I have had a CPR Bak-Pak for over a year and mine also grows coralline. However, mine is more specific to the output chamber rather than the in-take chamber where the cup is. I also have it growing on the pump which I have to scrape periodically. I have been extremely happy with this skimmer, although over the past several months it has become sluggish even though I have taken it apart and cleaned it thoroughly several times. I'm thinking only one year is a short time to have to replace a skimmer. If the coralline could be the problem for any HOB skimmer, how is it avoided, especially if it is in the tubes or the angle of the chambers prevents scraping? I have soaked all in vinegar water also.