type of fish?

[kaiserpup]

I currently have a small blue damsel and small black cap in a 30 gallon tank. I'd like to also get a small Flame Hawkfish and 1 other fish. I know I will probably have to get a larger tank or something as everything gets larger, but for now, can I put a 4th fish in this size tank?
Also what kind of fish will get along well with these other three fish? I will have a purple/pink fish, a blue fish, and then a red fish. So I'm thinking of one that will be green, yellow, black, white, or a mixture of colors. I thought about a tang, but I think they are too big, and a watchman goby looks like it would be too passive and I've read that mandarins are for experts only.
Any suggestions?

 

[daddyfish]

You should be fine I have a 20 gal tank 2domino damsels 1 yellow tail damsel 1 moran clown 1snow flake eel and 12 blue leg hermit crabs. I have had them for 5 mths now levels are great everything is great i wouldnt go any more than i did though you should not have any problems just keep check of your levels.

 

[twoods71]

You are looking at small slender fish so you may be OK.
If you do decide to go with 4 fish wait a while after adding the third fish and make sure your system can handle the bio load.
One problem that may pop up is aggression. When fairly aggressive fish start becoming crowded they tend to become very aggressive fish.