Line 29:
Line 29:
|-
|-
| Pipe diameter reservoir
| Pipe diameter reservoir
| Is equal to underdrain pipe diameter
| Is equal to underdrain [[pipe]] diameter
| 0.4
| 0.4
|-
|-
| Pipe bedding (''d<sub>b</sub>'')
| [[Choker course|Pipe bedding]] (''d<sub>b</sub>'')
| 50 mm (although commonly omitted altogether).
| 50 mm (although commonly omitted altogether).
| 0.4
| 0.4