I personally buy the coral from a tank - which I can observe - without pests - I have it bagged and drive it home 20 minutes - and put it in the tank once the temperature is matched (the LFS I go to uses the same lighting and parameters that I do). I tend to buy a bunch of coral and let the grow - there is no - 1 coral/week, etc - I would suggest that the best way to do this is to save until you can buy what you want and do it at once - as compared to weekly or monthly additions. Same with fish. The time you spend waiting - is money you're not spending on QT, etc. Again JMHO. It amazes me - how many people are adding things so often - in reality - that suggests a problem - rather than a successful tank.