Good day everyone

I have a Mayan Cichlid ( over a year old ) but he's lost a lot of appetite.
He used to eat heaps of stuff, but it's been about a 12 day time that he's eating less and less.
He was eating pellets, pond sticks and live insects (fom time to time).

He seems to be the "usual self" but eating much less.
Is it a normal attitude ?
He's also became more aggressive and enjoys digging the gravel, building up a "huge wall" on a side of the tank.

Thank you for your advice and comments.
If you could tell the sex, that would be highly appreciated as well !