Callum The Cat

Isabella

My encyclopedia says that Common Hatchetfish (grows up to 2.5") are peaceful shoalers that should be kept in groups. They should not be kept with any boisterous fish. Angelfish can be boisterous, especially when they breed.

As for the Rams, they can be kept with Angelfish AS LONG AS the tank is large enough for the Rams to run away and hide in case Angelfish get territorial. Angels and Rams are both Cichlids.

Don't know anything about Cockatoos.

Callum The Cat

Isabella

Look, I've never had Angels and Hatchetfish together in one tank, so I don't really know, but the above information is what I found in my Freshwater Encyclopedia. Maybe they could be OK if you provided lots of space and hiding spots, just like providing lots of space and hiding spots for Angels and Rams in one tank.