Some coconut water has a lot of potassium... I think about half a gram of potassium per serving, which I think is one cup. (nutritionfacts.org)
With more than 10 percent of the daily value for potassium per serving, both fresh bananas and banana powder qualify as good sources of the nutrient. (healthyeating.sfgate.com)
Avocados contain more potassium per serving compared to bananas, a high potassium fruit. (affecthealth.com)