Banggai Cardinalfish acting a little weird...
So last week I picked up 4 Banggai Cardinalfish ... they are pretty cool. The first few days all 4 of them swam around the tank, staying pretty close together. They were all eating and everything seemed fine.
Now the past few days I notice that 2 of them hide out in the caves or the back of the tank, while the other 2 continue to swim around the front of the reef and in the open water like before.
Now I read up on these fish and supposedly they are nocturnal and generally do hideout in caves, under overhangs, etc. during the day. Which is weird because none of the 4 were doing that at all the first few days in the tank.
So now I'm not sure which pair to be concerned with - the 2 that continue to swim around in the open or the 2 that seem to have reverted to their "natural" behavior?
I did notice something with the 2 that are now hiding out most of the time. Their gills are huffing and puffing quite a lot, almost like they can't breath or something. This is all new to me and I'm not sure what that means but it doesn't look like a good sign. Are these 2 sick or just not liking the new tank or something?
Or do I just need to wait it out since they are still new to the tank and just see if/how they settle in to a routine?