Pygmy Corydoras Bulging Eyes and Bruises

[Phatboyaa]

Hello everyone! I got sent here from another forum to ask about my Pygmy Cory. So recently I set up a walstad tank measured about 10 gallon. A little more after a week later I decided to add livestock a day ago because parameter seems stable enough. I add 20 red cherries and 10 pygmy Cory. All the cherries are fine but one thing I notice is that one Cory seems to have problem. One eye is bulging out and cloudy and there's red spots behind the head like bruises or scars (see pictures)

. Is there something wrong with him? One Cory already died within hours of introduction with the same symptoms, the rest looked fine so I chalked it off as bad stock or injury during shipment but now there's one more Cory with the same problem. I'm afraid it's infectious.