Ice that smells fishy is usually a result of unsealed food that is causing the odor of the food to be absorbed by your ice.
If you have an ice maker it can also be a result of the food odors in the freezer transferring to the ice maker and ice.
The black stuff in your ice maker is most often mineral buildup although in some cases it may also be mold.
Even with filtered water the minerals can come through and build up over time and lead to the black stuff in the ice maker.
It's also possible that there is a component within the ice maker, such as the ice mold or related parts, that has deteriorated or is releasing particles.
Inspect these components closely to ensure they are clean and not deteriorating.
If it's mold the mold can lead to all sorts of health risks, as pathogens like E. coli, norovirus, and salmonella can survive in the ice produced by the ice makers and ice machines.
This poses a significant threat, especially in environments where the ice maker isn't cleaned regularly.
If mold is present, you can add 3 cups of vinegar to the water line with a funnel and turn on the ice maker so that the vinegar runs through the dispenser.
Use a cup to catch the vinegar and use a toothbrush and rag to scrub the dispenser clean of any residue.
When there are black specks in the ice maker ice, it could be due to hard water deposits and a bad filter.
Check the water filter and make sure it is properly placed within its nook.