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Mystery Fish in a Koi Pond: Could It Be a Green Tench?

Description Match

5 inches, thin, wide head/mouth, single barbel pair, short flag-like dorsal fin, pale orange fading to white, peaceful. Matches green tench (Tinca tinca), a bottom-feeding cyprinid often sold for algae control.

Tench Behavior

They root in sediment, eating detritus and some algae. Compatible with koi and goldfish. Can grow to 12+ inches.

Verification

Search "green tench" images. Visit koi-z-are-us.20m.com for pond examples.

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