Four Sick Orandas ,

Question
Dear Chloe,
I need help your help on how to cure my fish. I started my tank two weeks ago and i just 4 big orandas in my 30 gal tank.   The water seem to be fine for a week but when I woke up today.The tank started to have a lot of bubbles forming on top   of the water and it smells. I just change my water last friday about 20%. I was worried so i changed another 20% of water again today. But I noticed the bubbles are still there and my fish are not as active as a few days ago. They are swimming around but not as much as before. Are they sick or I worry too much? >,< Please help me on this. Thank you so much

Answer
Hi Quan,
I think you are overfeeding your fish which results in foaming bubbles at the surface and a bad odour. Overfeeding can also cause bad water quality which is why your fish are not so active. Cut down on feeding and remove any uneaten food after 2 minutes. Keep up on the daily water changes and syphon the bottom of any rotting food.
Good luck!
Chloe.