Just like people (and plants) diseases are more likely to rear their ugly heads on fish that are already under some type of stress. Water temperatures that get too high, chemical problems in the water including improper pH, fish living in constant fear for their lives because of predators or by being pestered by children or well-meaning adults are all stresses that lower the disease resistance of fish in the backyard pond.

When fish become ill, they usually show one or more of the following symptoms:

• Stop feeding
• Sucking for air at the water surface
• Constantly rubbing up against plant pots or other objects in the pond
• Sores or spots on their skin
• Acting lethargic all the time
• Drastic loss of their usual coloration

If you have a fish that is showing symptoms and you suspect a disease, try to contact a veterinarian that has training in dealing with fish problems. Members of the local koi or water gardening clubs may also be sources of good information on dealing with fish diseases.

In the end, remember that a pond that is in balance will be far less likely to foster fish diseases or parasites.