One of the misconceptions about fish is that they will only grow to the size of their aquarium. This notion is extremely common, in fact, and an awful lot of people think that fish with potentially large sizes will stop or slow their growth as space in the aquarium vanishes. Unfortunately, this isn’t even remotely true. While it is true that growth rates slow with age, a large fish will get large. A tang won’t stay 2″ long just because you place it in a nano aquarium its entire life. So, listen to all of those tang police and give your fish an appropriately sized home.