I have seen red bugs attack other sps besides acro's. When I had them they were all over my M danae's as well. They are like spider mites and make webs and can be everywhere. I would treat the whole tank if it was me. When I did mine I lost my hermits, pm shrimp and most acro crabs. I still had a thriving pod population and no ill affect on my cleaner shrimp, but that can be hit & miss. No affect to my starfishes either but again hit & miss. It unfortunately didn't kill my killer crab.
