Do you have any other pictures? All I can see is a big purple blob approximately 1mm in width. If that is indeed it, then it's definitely NOT an acro red bug. Plus, I can't tell from the picture if that's actually an acro. If it isn't then that would be the best confirmation it's not a "red bug".
We need a much clearer and closer picture.
It's possible it could be a parasitic copepod or it could be a harmless amphipod.
How many eyes does it have if you can tell?