Are there some general rules for watts/ lighting required for different corals in a marine tank? thks!?

Answer 1

This really depends on the types of corals, the depth of your tank, type of lighting system you use, and distance from your lighting to your tank - really to many variables to get a "good" answer without knowing more about your set-up and what you're interested in keeping.

Some basics:
Some corals (like Tubastrea) require no special lighting - only those with photosynthetic algae (zooxanthellae) do. Even then, there are preferences as to the strength of the lighting.

Depending on where/how your coals were kept previously (store, supplier), many won't be able to withstand much more intense lighting - even if that's what they should have - you should place these lower in the tank and move them upward gradually.

As an alternative to the previous statement, if you have a suspended lighting system, and are just starting, you can raise your lights (you can also get "legs" for a light canopy).

The minimum I'd use is a double tube high output compact fluorescents - about 4-5 watts per gallon, if you have a relatively shallow tank. If you really want to get into a lot of corals, look into a metal halide system (or combined metal halide-compact fluorescent). Problem with the halides is that they get HOT! They also work best without a tank cover (less heat buildup, better penetration into the water, but more chance of fish jumping out). Halides are also more expensive.

For some more detailed info, I'd suggest the book "Corals" by Julian Sprung. There are photos of each coral, plus easy-to-follow charts on ratings for lighting needs, water movement requirements, feeding, aggression to other corals, where to place them in the tank, etc. Here's a link to a mail-order store I use which has a decent selection of lighting systems, so you can get an idea of what's available and pricing: http://www.thatpetplace.com/pet/product/categoryInfo.web?options.passInCategoryKey=22943

Answer 2

I am so bord