H2O is an Open Source, Distributed, Fast & Scalable Machine Learning Platform: Deep Learning, Gradient Boosting (GBM) & XGBoost, Random Forest, Generalized Linear Modeling (GLM with Elastic Net), K-Means, PCA, Generalized Additive Models (GAM), RuleFit, Support Vector Machine (SVM), Stacked Ensembles, Automatic Machine Learning (AutoML), etc.
There are some different ways to do this:
Use metalearner as base learners, keep level-one frame and pass this as the training frame
Use the blending_frame instead
Requested on StackOverflow: https://stackoverflow.com/questions/55378660/is-it-posible-to-make-a-stacked-ensemble-model-from-two-stacked-ensembles-models