I'd do the clown and the goby and leave it at that...unless you're going to run a huge sump. That way you'll have good movement at all levels of your tank. As stated above, maroons are aggressive and two in a tank that size are not likely to get along. Definitely wouldn't put all those fish in a 29G though...not enough water for that many fish. They may all be an inch now, but they will get bigger.