Gotta read the whole regulation....basically depends on your length, anchored in a designated anchorage area, or in a navigation channel. Being that I don'r intend to anchor overnight in a channel, I disposed of my anchor light, and if I needed to, there are other methods to bring attention to your boat:
(e) Vessels of less than 7 meters in length when at anchor. A vessel of less than 7 meters in length, when at anchor, not in or near a narrow channel, fairway, anchorage, or where other vessels normally navigate, shall not be required to exhibit the lights or shape prescribed in paragraphs (a) and (b) of this Rule.
(g) Vessels of less than 20 meters in length while at anchor in special anchorage. A vessel of less than 20 meters in length, when at anchor in a special anchorage area designated by the Secretary, shall not be required to exhibit the anchor lights and shapes required by this Rule.