Hello, I have a question about whether I should add all the fish at once or one by one. My new tank will soon be ready for new fish. It is a 20-gallon tank. I plan to have a pair of clownfish, a valentini puffer, a falco hawkfish, and a diamond goby. My friend advised that I should add the fish all at once, especially the "shy" fish first. If a "shy" fish is added later, it may be bullied by those already established, like the clownfish. If that happens, the fish might stop eating and die. I am hesitant to add them all at once as it's a new tank, and I'm worried they might all die. Any advice on which fish I should add first or if I should add them all at once? And I actually not sure which fish is more shy, goby and hawkfish? Thank you!