Makes sense to change it.
I changed mine last summer. It was just as you described and a diesel
upkeep course I took said to be prepared to change them when carbon chips build up. Makes sense to do it every 2 years as stated above. [make sure you replace the hose and really tighten the clamps!
A man who is not afraid of the sea will soon be drowned, he said, for he will be going out on a day he shouldn't. But we do be afraid of the sea, and we only be drowned now and again.
J.M.Synge, in The Aran Islands