HCA: Hermit Crab Association

So today I was doing a gender check on one of my crabs and I noticed so redness around the gill area. It didn't look swollen, just red. This worried me a little so I checked the other crabs and sure enough they had the same thing (though it looked more pink on the other ones). The first thing that came to mind was the humidity. I have always had low humidity (60-70%), but it never was a problem before. I all thought that maybe the mites were back (had a problem with them a few months back) but I didn't see any mites. Anyone know what's going on?

It should just be coloration! Many crabs will have pink or red markings in that area, especially if recently molted.

Definitely could be coloration.
Unrelated though, your humidity needs to be higher. Although it has not been a problem up to this point, it can cause problems long term. Have you looked into what you can do to raise your humidity?

Yes, I do know my humidity is too low and I am working on a solution. I added more ee to my substrate and got larger water bowls, I'm also misting them 3 times day instead of 2. This seems to be work so far but I still can't get it to 80 (that is my goal). I will keep trying but right now it's pretty stable at 73%.

What do you have as a lid/ cover on your tank?