At what point do you cut your loses

[SeaHorse_Fanatic]

Try looking into what is causing the problem. Low flow? Low light? High nutrients? Something touch it? Etc.

[Chin_Lee]

it depends on the rarity and price of the piece that I bought. If its rare, i frag until the very last polyp. If its a common piece, ba-bye.
the best part about sps is you can cut it down to the healthy tissue and glue that on a rock. It helps to increase your alkalinity/calcium to promote sps growth for the smaller frags.