For the sponge - try a blender. Seriously! Most are nonphotosynthetic with a few exceptions in the hobby but I have heard of seahorse keepers getting serveral varieties - throwing them in a blender then pouring them in the tank and letting it sit for a month.

Gorgonians - usually scrape some of the flesh back from the cut part to expose the 'stem' and glue that into a crevice works well. I'd give them swish in some fresh seawater and place them in good current. The latest issue of 'Coral' magazine has tips on fragging gorgs. The only ones I've kept and fragged were 'purple sea whips' probably Pseudopterogorgia guadalupensis?