...mention internal organs as the ammonia level in the blood rises (hyperammonemia). Get...into a real tank with a heater (unless they're Goldfish) and filter, and you can put as many flowers as you want into the bowl.
Re-pot it immediately. There is too much acid in coffee for most plants. Rinse the roots GENTLY and put in new soil and pot. You will have to clean the current pot with warm soapy bleach water to kill the fungus.