What interval is recommended for restocking fish after using rotenone?

The recommended restocking interval for fish after using rotenone is typically around 2-4 weeks. This timeframe allows for the toxic effects of rotenone to diminish sufficiently to ensure that the waterbody is safe for new fish populations. Rotenone is a piscicide that can eliminate fish by inhibiting their ability to absorb oxygen, thus it is crucial to wait until the toxicity levels drop to a point where they no longer pose a threat to newly introduced species.

Restocking too soon can lead to high mortality rates among the new fish, as residual rotenone might still be present in the environment. By waiting for about 2-4 weeks, fish health is better ensured, allowing the ecosystem to stabilize before the new stock is introduced.

Options reflecting shorter intervals, such as 1-2 weeks, may not provide enough time for the toxicity to clear, leading to possible negative outcomes for both the fish and the aquatic ecosystem. Conversely, intervals longer than 4 weeks may be unnecessarily extended, delaying the restoration of fish populations without significant ecological benefit.