Is the tank planted? I ask this because
Bristlenose Pleco have been known to chew holes in soft plants (and some not so soft).
If the present BN is for algae control, another will not likely be needed. If, however, you just like the fish, you should be OK with another. Males are territorial, so some chunks of bogwood to provide hiding spots. In a 55g with that, you're fine.
If you like the pleco i general, there are many other interesting species too, that would manage in a 55g. The Hypancistrus genus is loaded, and most remain under 5-6 inches. These are not vegetarian by nature, being omnivorous, so plants are not damaged.
Byron.