This pattern would work well for any clown fish.

Instructions:
Head:
Cast on 28 st in orange. Knit 2 rows.
Work rest of hat in Stocking Stitch.
Continue in Orange for 6 rows .
Join Black – work 1 row.
Change to White – work 2 rows.
Black – work 1 row.
Orange – work 2 rows.
Row 15: K2tog, K12, K2tog, K to end
Row 16: P2tog, P11, P2tog, P to end
Row 17: K2tog, K10, K2tog, K to end
Row 18: P2tog, P9, P2tog, P to end
Row 19 in black: K2tog, K8, K2tog, K to end
Row 20 in white: P2tog, P7, P2tog, P to end
Continue in White :
Row 21 cont. in white: K2tog, K6, K2tog, K to end
Row 22: P2tog, P5, P2tog, P to end
Row 23: K2tog, K4, K2tog, K to end
Row 24 in black: P2tog, P3, P2tog, P to end
Row 25 cont. in orange: K2tog, K2, K2tog, K to end
Row 26: P2 tog, P1, P2tog, P1
Cast off

Tail:
Cast on 4 in orange
Work in Stocking Stitch
Rows 1 – 3: Inc in first & last st (10sts)
Rows 4 – 6: Purl
Rows 7 – 9: Dec in first & last st (4sts)
Cast off 

Fins – Make 2:
Cast on 6
Row 1: Inc, K4, inc (8sts)
Beg Purl, SS 3 rows
Cast off

Top Fin – make 1:
Cast on 8
(K1,P1) rpt to end of row
(K1,P1) rpt to end of row
Cast off in rib

Making Up:
Join main body together and turn right side out.
With right sides out, fold fins, oversew the row ends and sew in place on the body.
Fold the tail naturally in half with the right side out and sew the row ends together, join to the body.
Attach top fin and add googly eyes to complete Nemo.