A humbug damsel.
'Deb' from 'Finding Nemo' is most like our species of fish the humbug damsels (Dascyllus aruanus).
I say "most like" because there are some notable differences. The film's creators have taken some creative license with this species, so they are quite loosely based upon real fish. For example, Deb is blue in the film and humbug damsels are black - also their tails are different. While I like the film, as an aquarist these are things that are hard to ignore!
In the film Deb believes she has a sister 'Flo', which is actually just her reflection. Having been in one of our tanks in scuba gear, you can see your reflection when you look at the glass, but you can also see through the glass and into the aquarium - so the fish can see you when you come to visit! Who’s watching who now eh? Don’t be inspired to tap on the tanks to get their attention though, the fish might think it's a bit rude and in some cases it can be stressful to the animals.
A lot of fish that see their reflection try to fight with it, this is because they recognise their species, and see them as a potential threat! If they’re in a school of fish this reflection is an outsider and if they’re solitary fish they’ll see it as a rival. I’ve not observed any of our humbug damsels talking to their reflection, but they are kept in quite a large tank and fish find their own spaces within tanks and tend not to venture away from them.
These fish grow at most to 10cm (4 inches) in length. In the wild they can be found in the Red Sea, and the Indian and Pacific Oceans in large groups above corals in reefs, or amongst the corals in smaller groups. They’re pretty territorial and quite aggressive when it comes to protecting their eggs. Males will court a female and invite her to spawn in their nests, the males then guard the eggs and fend off any fish that venture too close.
Feeding the fish at the Aquarium
The eggs hatch in 3-5 days. Their diet consists of zooplankton, small copepods, shrimps, clams, worms, and also algae. They can pick out these small inverts from the crevices of the rocks in our tanks, they also graze on the algae in our tanks. We feed them on fish flake and enriched mysis too, to make sure they have a nutritious and varied diet.