What have you tried and how did it end with marine GSPs?
What I had partly destroyed were hystrix birdnest, Caulastrea, Hammer, Acropora, a Gorgonian and small Zoanthids.
What has not been eaten after an initial bite are: Trees (Nephthea in this case), mushrooms and green Sinularia. Marcoalgae (red and green) have also not been eaten so far (it's always "so far" I guess).
I plan to try various Toadstools (green, brown, long and short polyps), gorgonians (again, different species), and larger Zoanthids as well as some more Sinularia and maybe manjanos and Kenya trees (maybe some other trees as well, and/or Klyxum).
Give a man a fish, and he'll eat for a day. Give a fish a man, and he'll eat for weeks.
My Puffers: Puffers I have kept: T lineatus T miurus A modestus T biocellatus C valentini C coranata C papuan C lorteti DPs suvattii burrfish T niphobles
Right now I've got a couple toadstools, a finger leather, Kenya Tree, some type of Xenia, Green Star Polyps, some kind of pink polyps, a couple Duncans, Hammer, Frogspawn, couple Ricordia, Galaxea(Tooth Coral), an open brain, a short tentacle plate coral, a Favites brain coral, several different zoas, a Hydnophora Grandis, and a Merulina ampliata(SPS). I also just(tonight) added a German Blue Polyp, a Pocillopora, and Torch coral which I don't have any reason to expect problems with but won't know for sure until tomorrow.
My 2 GSPs did pick at many of the first corals I got, they took several chunks out of my Duncan which was only my second coral making me doubt the whole reef idea, but after removing it to the refugium for a couple days then watching it like a hawk after reintroducing it I've had no problems. They've also left my other fish, a Blue Eyed Kole Tang, a Solo Fairy Wrasse and an Algae Blenny, alone, and while they do occasionally get the better of a snail or hermit my CUC has held up. Hopefully this remains a constant as they mature, I've had them for about 2 years now and they still don't have the look of mature GSPs.