| Hydros Argos Investment Limited | Private company limited by shares | Live |
| HYDROSA TRADING LIMITED | Private company limited by shares | Live |
| Hydroscience Resources Limited | Private company limited by shares | Live |
| HydroSeal Limited | Private company limited by shares | Dissolved |
| HYDROSEAL CANADA LIMITED | Private company limited by shares | Live |
| HYDROSEAL CANADA PIPING SYSTEMS CO., LIMITED | Private company limited by shares | Live |
| HYDROSEAL CANADA PRODUCT MANAGEMENT LIMITED | Private company limited by shares | Dissolved |
| HYDROSEAL CORPORATION LIMITED | Private company limited by shares | Live |
| HYDROSOFT LIMITED | Private company limited by shares | Live |
| Hydrosonic Limited | Private company limited by shares | Live |
| HYDROSPA LIMITED | Private company limited by shares | Live |
| HydroSpotless Company Limited | Private company limited by shares | Live |
| HYDROSTAR HK LIMITED | Private company limited by shares | Live |
| USA HYDRO-STOP (CHINA) LIMITED | Private company limited by shares | Live |
| HYDROSUN CANADA LIMITED | Private company limited by shares | Live |