How to treat stress ich

A fish with ich tends to look like it has tiny crystals on its body, like someone sprinkled salt on it. We tend to notice ich on the fins first since there’s less slime coat in those areas and it’s easier for the parasite to target. Other symptoms may include loss of appetite, rapid breathing, fish rubbing their bodies against surfaces, lethargy, and hiding behavior.

If your fish has ich that comes from an external parasite, you will see five spots today and then maybe 35 spots tomorrow. However, some fish get “stress ich” or stress spots, which evenly covers the entire body (not just the fins). If you see five spots today and five spots tomorrow with no increase, this may be stress ich instead and will not necessarily respond to the ich medication.

As a rough analogy, ich is like chickenpox (which are spots caused by an infectious microbe), whereas stress ich is like stress acne (which are spots caused by hormones and are not contagious). The treatments for chickenpox versus stress acne are very different, and the same applies to ich versus stress ich. If you believe your fish has stress ich, give it an environment with plenty of clean water, high-quality foods, and low stress. Eliminate any sources of stress, such as:

• Wrong water parameters (e.g., pH, temperature, ammonia, nitrite)
• Current that is too strong
• Bullying or being outcompeted for food by stronger fish
• Lack of decorations or plants that block line of sight (so the fish constantly has to defend its territory)
• Old fish food that has gone bad

If the fish is active, eating well, and not gaining more spots, then usually the stress ich will disappear on its own after several weeks or months. For more information on how to treat normal ich, read our full article here.