Two years old, I thought it was a male for the longest time but the dorsal fin is the same size as the other plain female I have. The caudel fun has no black mark at the base though, so I'm confused.
Looks like a young male due to the colour in the fins, however it shouldn't have a round tail. Round tail normally means a female. It could have a deformed tail and then it's a male.
It has a njisseni/panduro shaped tail, a low dorsal with linebred cacatuoides set of markings, and attributes of both sexes. I've had quite a few intersex fish show up in Pelvicachromis over the years, but that one looks inter-sex and inter-species. Whatever it is, it's a cool looking beast.
It never displays in courting, only in bullying. Side by side, the one the right is a little washed out due to sand color. But both of these came from the same store tank 2 years ago
The fish on the right has the wrong body colour for a female A. cacatuoides. It should be a lot more yellow rather than cream. However, the fins are correct for a female.
Has it ever looked yellow?
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You have blue green algae on the sand. It loves dry food, low oxygen levels, calm water and nutrients. If it gets worse it can affect the fish that live near the bottom. Regular gravel cleaning and big water changes usually help get rid of it.