| Filters | Cells | Depth (cm) | Material | Granulometry | Plant |
| FV1 | FV1a | 70 | Flint | 3 - 8 mm | Typha (Phragmites) |
| FV1b | 70 | Granite | 3 - 8 mm | Typha (Phragmites) | |
| FV1c | 15 | River gravel | 3 - 8 mm | Typha (Phragmites) | |
| FV2 | FV2a | 90 | River sand | d10 = 0.27 CU = 3.6 | Phragmites |
| FV2b | 70 | River sand | d10 = 0.27 CU = 3.7 | Phragmites |