LPS corals, 13 of them.

LPS means large-polyp stony: a hard calcium-carbonate skeleton carrying fleshy polyps big enough to see close up. They lay down that skeleton from the water, so alkalinity, calcium and magnesium have to stay steady rather than merely be present - but most tolerate moderate light and gentle flow, and many will visibly take a meaty food, which makes them satisfying to keep. They suit a reefer with a few stable months behind them who wants colour and movement without the swings SPS punish. The trade-off is space: torches, hammers and brains extend sweeper tentacles at night and will chemically burn a neighbour they can reach. Plan the rockwork with real gaps, not the gaps a fresh frag appears to need.