Hi Sally. Welcome to
Talking Reef.
Regarding flow - this is really dependent on the corals you plan on keeping. In general, SPS require more flow than LPS, which require more flow than soft corals. There are, of course, many exceptions to this rule! The amount of flow you have is a good start,
IMO. More important is to make the flow random (which you are doing with timers) and to make sure that the corals do not get blasted with a strong direct output from you powerhead. Many corals tend to adapt to varrying conditions. I have a huge amount of plusing Xenia that has grown right into the direct output of a Seio 820. I was told that it would not survive. Not only is it surviving, but it's growing even faster.
I know that some people have tanks set up for fishes from specific regions, the most popular being fish from the Red Sea. This is actually not a bad idea, as the
salinity of the red sea is a bit higher than the norm. That said, I think you will find most people want to collect their favorite species of fish and corals, and these tend to come from different areas. The discision many people face is whether to go fish only or reef, as there are some amazing fish that can't be kept in a reef tank due to picking on or consuming corals and inverts. A few of us lucky ones get to set up a tank of each. You are similar in having a freshwater and saltwater tank.
Good luck with the tank. Please keep us up to date.
