[bluespotjawfish]

Did this sponge get exposed to any air? You probably already know not to expose it to air, but just in case I thought I'd mention it. It could bounce back, but keep it in a flow area. Also check how much light it is getting. It may not want as much as you have it under. Make sure you have an adequate cleaning crew (small crabs) to keep the dying stuff picked off of it.

Good luck!