My Poor Clown Fish

[mike31154]

Lid? You have a lid on your tank? Tell us more. I tend to agree with intarsiabox in that your O2 may be low if the lid you're referring to is keeping things tight. There has to be a good gas/air exchange at the water surface and your lid may be hampering that process. The more fish/livestock you add, the more O2 is required.

Best to keep the clownfish numbers to 1 or 2 if they are paired. Others will eventually be taken out by the dominant pair in a closed system.