Fish kills in ponds and lakes may occur at any time during the year from a variety of environmental and biological factors. Common causes of fish kills include summer and winter oxygen depletions, diseases and parasites, pollution, and thermal stress during breeding season. In some cases, there's not much that can be done to prevent fish kills. Proper construction, good watershed maintenance, and careful use of toxic materials in and around the pond, however, can go a long way toward preventing fish kills.
Common Causes of Fish Kills
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