Phalaenopsis with disease

[orchidgirl610]

Hello. This is my first post however I have been reading helpful posts on here for a while. I wondered whether anybody can help me? I have a phalaenopsis orchid which I have had for a couple of years. It was a rescue originally but is currently flowering and has a healthy root system. Last summer it started to develop yellow spots on a couple of its leaves which I put down to too much light/heat. However, it seems to be progressing and as a relative newbie to understanding orchids, I'm unsure whether this is something more sinister that needs treating? The older leaves are getting worse and it is also now apparent on one of the newest leaves. I have done some research but have been unable to come to a final conclusion about what it may be. I wondered about mites but when I wipe the bottom of the leaf, there is nothing on the tissue? A couple of the flower spikes are also now going black which worries me. I'd hate to lose this orchid and am desperate to know what I can do for it? I have also attached a photo of a deeper green leaf which belongs to a second phalaenopsis I have. I'm concerned about the white specks on this one and the patterning on the leaf? Many thanks, Sarah