Actually, It's Scleractinian, as in S
Scleractinia - Wikipedia, the free encyclopedia
Unless you have a tank that's loaded with these, (and when I say loaded, I don't mean twenty 1" frags, I mean mature colonies) you will be able to replace all elements with a simple water change regimen with a reef grade salt mix.
This 60" x 30" x 25" tall tank that used to be in my basement was not dosed ever, and no calcium reactor in sight. Weekly water changes kept all of these football and basketball sized colonies growing and healthy-
As was this 8' x 24" x 17" tall coral tank-
I don't know if you can make it out, but there is a 14" clam in there as well.
Also, in terms of lighting, watts per gallon isn't a very good rule to go by due to individual efficiency per watt.
T5's are every bit as capable for SPS
as metal halide is. LEDs however, are much more potent than both, providing you choose the right unit.