Adding Corals etc
 

What's a general time frame a tank should be up and running for before adding corals etc. What are other factors to be aware of before adding corals...

It's important to have a stable tank. By this I mean. Ammonia = 0, Nitrite =0 and Nirtate is <20ppm. After the tank cycles generally you will get several algae blooms it's best to wait them out before adding anything. Plus you will want to ensure your CA is around 400 your Alk is around 8 and your PH is at 8.2 to 8.4

What he ^ said. But I wouldn't add corals unless the Nitrate is less than 5ppm. Generally, it's a good idea to wait around 2-3 months before adding corals unless you're more experienced. Better safe than sorry.

Some tanks are never ready for corals because people don't care for their tanks well enough or are naive to the care.