The cave openings measure approximately 2.25" wide by 2" tall by 6" deep, with a backing to create a dark spawning cave. Although Bristlenose plecos are not very picky about caves, they prefer a cave that is slightly wider than the males pectoral fins, so please make sure these caves are an appropriate size for your fish before purchase. For smaller bristlenose and hypancistrus plecos, I also have spawning caves and condos for them available on my store!

Please let me know if you have any questions!