In previous work, we provided static domain and parameter datasets for the National Water Model (NWM) and Parflow (PF-CONUS) on demand, at regional watershed scales. We extend this functionality by connecting existing cloud applications and tools into a virtual ecosystem that supports extraction of domain and parameter datasets, execution of NWM and PF-CONUS models, and collaboration. This work leverages existing technologies such as the CUAHSI HydroShare (www.hydroshare.org) data repository, Jupyter Notebooks, Docker containers, Binder computing environments, and model specific subsetting codes. This presentation will discuss the cyberinfrastructure design of our cloud-based ecosystem of tools for working with CONUS model domain and parameter datasets, as well as highlight use cases for research, education, and reproducible science.