I recently bought a captive bred banded multifasciatus angelfish, he looks very small, any suggestions?

[Grey L]

I recently bought a captive bred banded multifasciatus angelfish, he looks very small, any suggestions?
About food, feeding frequency and other considerations.
Currently, my seawater salinity is kept at 1.020, the temperature is kept at 25 degrees, the water is changed once a day, and the brine larvae are fed four times a day.
At present it has not eaten any other meat and feed.

 

[KrisReef]

Try pods?
Try schucked live clams. Drop in a 1/2 shell and see if it will pick at it.
LIve worms.
Mastick (Not sure of the spelling- Paste food. Nutramar