I've been keeping Goldflakes for over 20 years. I've kept them to the point they were spawning in captivity. But no matter what I have tried at that size they never survive for me.
For me success is 100% when they are about 2.5" and the spot is gone and the black on the dorsal fin is almost half way to the head.
I know this isn't the supportive news you wanted to hear. And I am sorry because they are beautiful fish and they are not inexpensive.
Since Bali Aquarich started captive breeding the Goldflakes and release them to the US Market I have had 6 go into my tanks and gotten 8 others for friends. And sadly there are only 2 still alive and those are in my tank but they were older when I got them. I have had the current pair for over a year now.
Tomorrow (Thurs) I have a second pair arriving from Bali Aquarich. These are over 2.5". There are also some juvenile wild Goldflakes in the marketplace in the last few months. Even with these in the last 20 years I haven't had success with the tiny ones. I do find that the wild ones have a little richer colors - but the Captive Bred aren't slouches. While my current pair have adult colorations they are only about 4.25". In my experience the colors don't burst on these fish until they get to 6"+
These 3 went into 3 different aquarium systems. 3 different intense reef keepers - None ot them made it to 10 days in hobbyists tanks.
These 3 arrived on 6-21-23. The one in the center was a tad larger and even in the acclimmation bucket started kicking the butt of the other two. The big one was place in one of my 180g outdoor sunlit frag tanks. The other 2 immediately went into my 750g reef.
This is the Goldflake that went into the outdoor frag tank taken on 8-12-23. Growth rate was better in the sunlit tank and color was much better. The frag tank is not fed - all fish must hunt for what they want to eat. This fish was about 3.25" in Mar of 2024 when a horrible raccoon snaked the bright yellow fish out of the tank.
Dave B