Seeing lots of SPS and Zoa recommendations, I'll go to bat for Duncan. Do you have one already? In my experience great growth rate, don't break the bank, peaceful, and beautiful. Mine has gone from 6 heads to 16 in about a year....Likely time to frag it.Have come to appreciate that corals don’t have to be expensive to be colorful, grow fast, and have interesting shapes/textures.
Please share pics and names your non expensive corals! Looking for more ideas! Here are some of mine.
Spongodes
Toxic Green SPS, Red Serarosa, & Green Monti