Conditioning

Conditioning is the process of preparing our fish physically in the weeks before spawning, and it has a direct impact on egg quality, milt viability, and overall spawn success. Begin conditioning 4 to 6 weeks before your target spawning window.

Feeding

During this period, we can switch our fish to a high protein diet of 40 percent protein or more, using quality koi pellets, silkworm pupae, or other protein rich foods. Feed multiple small meals daily rather than one large feeding to maximize nutrient absorption without compromising water quality.

Water quality

Water quality during conditioning is equally important. Maintain clean, well oxygenated water with stable parameters. Ammonia and nitrite should be at zero, nitrates kept low, and pH stable between 7.0 and 8.0. Perform regular water changes to keep conditions pristine.

Water temperature

Some breeders do a partial water change with slightly cooler water in the weeks before spawning to mimic the natural seasonal transition that triggers breeding behavior. This temperature fluctuation signals to the fish that spawning season is approaching.

Keepsakes

The goal of conditioning is to bring both male and female fish to peak reproductive readiness at the same time. A well-conditioned female will be visibly full and rounded with eggs. A well-conditioned male will be active, attentive, and produce milt readily. Fish that are underfed, stressed, or kept in poor water conditions going into spawning season will produce fewer eggs, lower quality milt, and reduced fertilization rates. The investment you make in conditioning directly determines the quality of your spawn.

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