A polarized filter would eliminate the reflection. I used to do wedding shoots back in the 70's and 80's. I'm not sure if they make anything like that for an iPhone. So I thought I'd check real quick.View attachment 99788
Not a great photo as this is cropped from an iphone pic. This is the local snake-necked turtle I try to see every time I go to the lake. He/she has a shell maybe about 30cm long, and it's covered in algae. It's looking up at me here. I'm shooting directly down from the jetty seen in the previous pic but this time on a less flooded day! These animals are hard to photograph because of the water reflections, so I've had to increase the contrast to make it more visible. They're endangered so I feel very lucky to see this fella as often as I do.