My water out of the tap is soft and I use a decent amount of driftwood so it tends to stay that way and my female has cloudy eyes while my males eyes are much less so. As you said it maybe from trauma, scratches as Trachys are fairly clumsy in my experience. Well in their travels during the day when the tank is well lit. Being a driftwood cat they are primarily nocturnal and I believe despite their boldness light inhibits their ability to see properly and so causes them to bump into things from time to time.
And it maybe just me but it seems quite a few nocturnal cats tend to have a bluish tinge to their eyes. Since their eyes have evolved to see in the dark perhaps the cornea is different, thicker? To help keep light out so as not to damage their sensitive lens from light during day time movement or from damage that is more likely to occur during night time movements? Or maybe the cornea thickens the more light they expose themselves to protect the sensitive parts of the eye from light?
What kind of Pseudopimelodidae is that? Bufonius? Pseudopimelodidae are another one of my favorites to keep, ever since my first Cephalosilurus Apurensis. Currently I'm keeping 3 Batrochoglanis sp.(2) all around 3-4 inches. I don't know if they're voracious or extremely conspecific aggressive as just yesterday I found one of them with one of his fellows halfway down his mouth despite being nearly if not identical in size. After uttering a short high pitched shriek I immediately separated the two with both coming out more or less no worse for the wear.
By the way I did search for the threads using your username and Pseudopimelodidae and Exotic Fish Shop in several searches but couldn't find them. I think the latest searh results where 2019.
