I asked if the dat was in the same tank because they are prone to getting cloudy eye if there are issues with the water and if not treated it can lead to blindness.
So after a year , my larger armatus now about 12" decided to go on a hunger strike . The smaller. 9" one is eating fine as well as the 3 rays and the dat.
Something is bugging him as he's just staying in one spot and not paying attention to food, looks healthy. , clear eyes ect