Goldfish "Acting Crazy": Spawning Behavior

What You're Seeing

Koi pond (1 yr): 2 koi, 1 oranda, 1 black moor, 1 calico fantail, 2 shubunkin. Fish chasing oranda and shubunkin, pushing them out of water.

Diagnosis: Spawning

Classic goldfish spawning behavior. Males chase females, bump them to release eggs. Oranda and shubunkin are likely females. Fancy goldfish (oranda, moor, fantail) get battered worse than single-tails (shubunkin).

Action

1. Separate injured female to hospital tank with MelaFix, salt.
2. Add spawning mops (nylon rope bundles) for egg deposition and female refuge.
3. Do not interfere otherwise – it's natural.

Risk

Spawning can kill females from exhaustion/injury. Fancy varieties most vulnerable.

Reference

Goldfish breeding guide: fishpondinfo.com/gfish3.htm.