Does the rainbowfish sharing the exhibit with the lungfish? And what kind of rainbowfish (scientific name please) are in/at the LAIR? On the recommended list at the L.A. Zoo homepage there is only the term "Australian Rainbowfish" (could be dozens of species).
The rainbow fish does share the same exhibit as the lungfish, along with Fly River turtles and archerfish too. The scientific name of the rainbow fish is not given on the sign as I recall. If you ask on the LA Zoo's Facebook page they will probably be able to tell you, or maybe someone here does know...