They don’t swim around a ton. They burrow but they poke their heads out all the time. If you’re looking for something that swims around a lot I love my orchid blenny. Very nice color and very active but I also am looking to get a canary blenny which I’m super excited about. Its body is shaped similar to a female mahi mahi but it’s all yellow and it tends to hang out in the middle of the water column. My lfs said it’s a good community tank addition, it’s reef safe, and not super delicate but not as hardy as others so best to add it to a fully cycled tank that’s at least 3-4 months old which I assume isn’t an issue for you. The scooter blenny is so cool too. Very small fish but scoots along the rocks and sand bed like a goby would and is bright red. Might not be a bad option to look into as well