What caring of fish is this?

Someone told me it's called a "green decon" but I can't find that kind of fish on any website. She said that "these change colour near their mood!!" and that sounds really cool. Did she accidentally misspell it or something? What kinds of fish would change colors like that?
maybe its a betta fish
All fish can "exchange colour" to a degree depending on mood - those moods being fear/illness, territorial/mating display and normal. The first man going pale, the second being that bit more vibrant than commonplace.

"Green decon" - did they mean green dragon, demon or something else? Common names in any casing could mean anything and apply to sometimes vast numbers of fish. Go back to that entity and ask for a latin name, not a common name (common name are usually invented by pet stores anyway!) If they can't give you one they're chitchat out their butt!
Answers:    It is not "green decon fish" the right residence is Green Demon Fish. This fish can change body color if this fish saw some female green demon fish.
Did not know a fish changed colors.
Are you referring to tropical freshwater or marines. There are some new fishes that there is not known more or less them. There is a 'Green Terror' which is a cichlid and which you find in the link below.

I did a search for Petco Pet supplies and they own no fish that's called Green deacon---Green beacon---Green demon. Perhaps you could try their website.
While I was looking 4 ur fish which I cud not find at adjectives I came across this, it's also quite interesting. Betta, also known as the Siamese combat fish, common name of a small freshwater fish native to Southeast Asia. Cultivated bettas may be of any color but most commonly are red, blue, or turquoise. The color within males becomes more vivid when the fish is courting or otherwise aroused.
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