The cloudiness was/is probably a bacterial bloom on account of the increase in ammonia. You are talking about pH when you need to be watching all parameters ammonia, nitrite and nitrate along with pH, and if you are worried about pH you also need to watch kh and gh. Tds is important also to a degree. I don't think keeping a ray for close to a year and a half is a major accomplishment tbh. I agree with
duanes
tank is to small for those fish. Rays need alot of room and clean water as does the cat fish. 180 sounds like a big tank but honestly is on the very small end of the scale when talking about the fish you are trying. I would take this as a lesson learned and look in to other types of fish better suited to that size tank or get a much larger tank first.