I’ve had this yellow watchman goby for about two months. He paired up with a Randall’s pistol shrimp and would come out to grab food a few times a week. Today was the only time he's come off the sandbed, he's been swimming around the top of the tank and hovering near the glass. His color was fine earlier but is now looking a little pale, but these photos were taken at night. I've read about YWG going pale at night and back to yellow in the morning. Some posts say that their YWG glass surfs often and it's not something to be too worried about, while others say it could be indicative of ammonia spiking, flukes or another parasite/disease. Before today, he was extremely skittish. He would come out and surf the sand bed but if you walked up he would dart into his burrow immediately. Now while he's swimming in the water column he has no reaction to me walking close up to the tank or taking pictures with my phone almost pressed up to the glass. A fish who has never come out to the top of the tank before in the two months of having him, to suddenly swim around the water column for hours at a time, as well as going from extremely skittish to perfectly "sociable" in a day. None of my other fish have paid him any attention or even swam up to up. He has the pistol shrimp buddy and has been establishing his burrow in the same place since I got him. All of the post I've read about similar behavior have been when the YWG has just been added, not after they've had a designated hiding spot for a couple months. I have a tank lid so he can't jump and an aerator running. Don't think lack of oxygen is an issue, he's not gasping either. None of my other fish or soft corals are acting/looking abnormally and corals have actually been looking better recently. I plan on doing a water change and maybe a freshwater dip, is there anything else I could do to determine what's going on with him? I have no idea if I'm overreacting or if I should expect a dead fish soon.