diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f4d042f003042319b3867857b756665a2aa3ddfc..eacbe3e26323e0a0bf1579cba53e2e12ecfd27c0 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -42,7 +42,7 @@ tests (from scratch):
     - ./CI/update_badge.sh > /dev/null
   script:
     - pip install --upgrade pip
-    - pip install numpy wheel six
+    - pip install numpy wheel six==1.15.0
     - zypper --non-interactive install binutils libproj-devel gdal-devel
     - zypper --non-interactive install proj geos-devel
     #    - cat requirements.txt | cut -f1 -d"#" | sed '/^\s*$/d' | xargs -L 1 pip install
diff --git a/HPC_setup/requirements_HDFML_additionals.txt b/HPC_setup/requirements_HDFML_additionals.txt
index 26e335d56d014abfb20ea68010c029660f492443..b2a29fbfb353f24d8c99d8429693022ea1fd406f 100644
--- a/HPC_setup/requirements_HDFML_additionals.txt
+++ b/HPC_setup/requirements_HDFML_additionals.txt
@@ -10,6 +10,7 @@ chardet==4.0.0
 coverage==5.4
 cycler==0.10.0
 dask==2021.2.0
+dill==0.3.3
 fsspec==0.8.5
 gast==0.4.0
 grpcio==1.35.0
diff --git a/HPC_setup/requirements_JUWELS_additionals.txt b/HPC_setup/requirements_JUWELS_additionals.txt
index 26e335d56d014abfb20ea68010c029660f492443..b2a29fbfb353f24d8c99d8429693022ea1fd406f 100644
--- a/HPC_setup/requirements_JUWELS_additionals.txt
+++ b/HPC_setup/requirements_JUWELS_additionals.txt
@@ -10,6 +10,7 @@ chardet==4.0.0
 coverage==5.4
 cycler==0.10.0
 dask==2021.2.0
+dill==0.3.3
 fsspec==0.8.5
 gast==0.4.0
 grpcio==1.35.0
diff --git a/mlair/data_handler/abstract_data_handler.py b/mlair/data_handler/abstract_data_handler.py
index f085d18bb8d33839a0e3b5f6f3d5ada92134e7f6..419db059a58beeb4ed7e3e198e41b565f8dc7d25 100644
--- a/mlair/data_handler/abstract_data_handler.py
+++ b/mlair/data_handler/abstract_data_handler.py
@@ -55,3 +55,6 @@ class AbstractDataHandler:
     def get_coordinates(self) -> Union[None, Dict]:
         """Return coordinates as dictionary with keys `lon` and `lat`."""
         return None
+
+    def _hash_list(self):
+        return []
diff --git a/mlair/data_handler/data_handler_kz_filter.py b/mlair/data_handler/data_handler_kz_filter.py
index 78638a13b4ea50cd073ca4599a291342fad849d4..1f2c63e58c7eaab645f074ac953d2f05d8ba09fd 100644
--- a/mlair/data_handler/data_handler_kz_filter.py
+++ b/mlair/data_handler/data_handler_kz_filter.py
@@ -8,6 +8,7 @@ import numpy as np
 import pandas as pd
 import xarray as xr
 from typing import List, Union
+from functools import partial
 
 from mlair.data_handler.data_handler_single_station import DataHandlerSingleStation
 from mlair.data_handler import DefaultDataHandler
@@ -22,6 +23,7 @@ class DataHandlerKzFilterSingleStation(DataHandlerSingleStation):
     """Data handler for a single station to be used by a superior data handler. Inputs are kz filtered."""
 
     _requirements = remove_items(inspect.getfullargspec(DataHandlerSingleStation).args, ["self", "station"])
+    _hash = DataHandlerSingleStation._hash + ["kz_filter_length", "kz_filter_iter", "filter_dim"]
 
     DEFAULT_FILTER_DIM = "filter"
 
@@ -38,10 +40,7 @@ class DataHandlerKzFilterSingleStation(DataHandlerSingleStation):
     def _check_sampling(self, **kwargs):
         assert kwargs.get("sampling") == "hourly"  # This data handler requires hourly data resolution
 
-    def setup_samples(self):
-        """
-        Setup samples. This method prepares and creates samples X, and labels Y.
-        """
+    def make_input_target(self):
         data, self.meta = self.load_data(self.path, self.station, self.statistics_per_var, self.sampling,
                                          self.station_type, self.network, self.store_data_locally, self.data_origin)
         self._data = self.interpolate(data, dim=self.time_dim, method=self.interpolation_method,
@@ -54,9 +53,6 @@ class DataHandlerKzFilterSingleStation(DataHandlerSingleStation):
         # import matplotlib.pyplot as plt
         # self.input_data.sel(filter="74d", variables="temp", Stations="DEBW107").plot()
         # self.input_data.sel(variables="temp", Stations="DEBW107").plot.line(hue="filter")
-        if self.do_transformation is True:
-            self.call_transform()
-        self.make_samples()
 
     @TimeTrackingWrapper
     def apply_kz_filter(self):
@@ -88,6 +84,15 @@ class DataHandlerKzFilterSingleStation(DataHandlerSingleStation):
         return self.history.transpose(self.time_dim, self.window_dim, self.iter_dim, self.target_dim,
                                       self.filter_dim).copy()
 
+    def _create_lazy_data(self):
+        return [self._data, self.meta, self.input_data, self.target_data, self.cutoff_period, self.cutoff_period_days]
+
+    def _extract_lazy(self, lazy_data):
+        _data, self.meta, _input_data, _target_data, self.cutoff_period, self.cutoff_period_days = lazy_data
+        f_prep = partial(self._slice_prep, start=self.start, end=self.end)
+        self._data, self.input_data, self.target_data = list(map(f_prep, [_data, _input_data, _target_data]))
+
+
 class DataHandlerKzFilter(DefaultDataHandler):
     """Data handler using kz filtered data."""
 
diff --git a/mlair/data_handler/data_handler_mixed_sampling.py b/mlair/data_handler/data_handler_mixed_sampling.py
index c62e18f2b69c5cc33d1bd86f5f288b61f53cdaf3..86e6f856b7bf061287261ae711063d71ed7c8963 100644
--- a/mlair/data_handler/data_handler_mixed_sampling.py
+++ b/mlair/data_handler/data_handler_mixed_sampling.py
@@ -12,6 +12,7 @@ import inspect
 from typing import Callable
 import datetime as dt
 from typing import Any
+from functools import partial
 
 import numpy as np
 import pandas as pd
@@ -54,15 +55,9 @@ class DataHandlerMixedSamplingSingleStation(DataHandlerSingleStation):
         assert len(parameter) == 2  # (inputs, targets)
         kwargs.update({parameter_name: parameter})
 
-    def setup_samples(self):
-        """
-        Setup samples. This method prepares and creates samples X, and labels Y.
-        """
+    def make_input_target(self):
         self._data = list(map(self.load_and_interpolate, [0, 1]))  # load input (0) and target (1) data
         self.set_inputs_and_targets()
-        if self.do_transformation is True:
-            self.call_transform()
-        self.make_samples()
 
     def load_and_interpolate(self, ind) -> [xr.DataArray, pd.DataFrame]:
         vars = [self.variables, self.target_var]
@@ -83,6 +78,12 @@ class DataHandlerMixedSamplingSingleStation(DataHandlerSingleStation):
         assert len(sampling) == 2
         return list(map(lambda x: super(__class__, self).setup_data_path(data_path, x), sampling))
 
+    def _extract_lazy(self, lazy_data):
+        _data, self.meta, _input_data, _target_data = lazy_data
+        f_prep = partial(self._slice_prep, start=self.start, end=self.end)
+        self._data = f_prep(_data[0]), f_prep(_data[1])
+        self.input_data, self.target_data = list(map(f_prep, [_input_data, _target_data]))
+
 
 class DataHandlerMixedSampling(DefaultDataHandler):
     """Data handler using mixed sampling for input and target."""
@@ -104,25 +105,14 @@ class DataHandlerMixedSamplingWithFilterSingleStation(DataHandlerMixedSamplingSi
     def _check_sampling(self, **kwargs):
         assert kwargs.get("sampling") == ("hourly", "daily")
 
-    def setup_samples(self):
+    def make_input_target(self):
         """
-        Setup samples. This method prepares and creates samples X, and labels Y.
-
         A KZ filter is applied on the input data that has hourly resolution. Lables Y are provided as aggregated values
         with daily resolution.
         """
         self._data = list(map(self.load_and_interpolate, [0, 1]))  # load input (0) and target (1) data
         self.set_inputs_and_targets()
         self.apply_kz_filter()
-        # lazy data loading on first time if possible
-        # * store the kz data locally in data path under different folder /e.g. kzf_data
-        # * create a checksum for the name and reuse this data always if checksum fits (this will replace all previous
-        #   steps and save a lot of computation time.
-        # lazy create of subsets by reusing as much as possible
-        # * start here when using preprocessed data, select new start and end
-        if self.do_transformation is True:
-            self.call_transform()
-        self.make_samples()
 
     def estimate_filter_width(self):
         """
@@ -136,14 +126,24 @@ class DataHandlerMixedSamplingWithFilterSingleStation(DataHandlerMixedSamplingSi
         new_date = dt.datetime.strptime(date, "%Y-%m-%d") + dt.timedelta(hours=delta)
         return new_date.strftime("%Y-%m-%d")
 
-    def load_and_interpolate(self, ind) -> [xr.DataArray, pd.DataFrame]:
-
+    def update_start_end(self, ind):
         if ind == 0:  # for inputs
             estimated_filter_width = self.estimate_filter_width()
             start = self._add_time_delta(self.start, -estimated_filter_width)
             end = self._add_time_delta(self.end, estimated_filter_width)
         else:  # target
             start, end = self.start, self.end
+        return start, end
+
+    def load_and_interpolate(self, ind) -> [xr.DataArray, pd.DataFrame]:
+
+        start, end = self.update_start_end(ind)
+        # if ind == 0:  # for inputs
+        #     estimated_filter_width = self.estimate_filter_width()
+        #     start = self._add_time_delta(self.start, -estimated_filter_width)
+        #     end = self._add_time_delta(self.end, estimated_filter_width)
+        # else:  # target
+        #     start, end = self.start, self.end
 
         vars = [self.variables, self.target_var]
         stats_per_var = helpers.select_from_dict(self.statistics_per_var, vars[ind])
@@ -155,6 +155,13 @@ class DataHandlerMixedSamplingWithFilterSingleStation(DataHandlerMixedSamplingSi
                                 limit=self.interpolation_limit[ind])
         return data
 
+    def _extract_lazy(self, lazy_data):
+        _data, self.meta, _input_data, _target_data, self.cutoff_period, self.cutoff_period_days = lazy_data
+        start_inp, end_inp = self.update_start_end(0)
+        self._data = list(map(self._slice_prep, _data, [start_inp, self.start], [end_inp, self.end]))
+        self.input_data = self._slice_prep(_input_data, start_inp, end_inp)
+        self.target_data = self._slice_prep(_target_data, self.start, self.end)
+
 
 class DataHandlerMixedSamplingWithFilter(DefaultDataHandler):
     """Data handler using mixed sampling for input and target. Inputs are temporal filtered."""
@@ -175,6 +182,7 @@ class DataHandlerSeparationOfScalesSingleStation(DataHandlerMixedSamplingWithFil
     """
 
     _requirements = DataHandlerMixedSamplingWithFilterSingleStation.requirements()
+    _hash = DataHandlerMixedSamplingWithFilterSingleStation._hash + ["time_delta"]
 
     def __init__(self, *args, time_delta=np.sqrt, **kwargs):
         assert isinstance(time_delta, Callable)
diff --git a/mlair/data_handler/data_handler_single_station.py b/mlair/data_handler/data_handler_single_station.py
index a894c635282b5879d79426168eb96d64ff5fa2a2..0497bee0ae6b6a72301181ef5453dd40f479e5af 100644
--- a/mlair/data_handler/data_handler_single_station.py
+++ b/mlair/data_handler/data_handler_single_station.py
@@ -5,9 +5,11 @@ __date__ = '2020-07-20'
 
 import copy
 import datetime as dt
+import dill
+import hashlib
 import logging
 import os
-from functools import reduce
+from functools import reduce, partial
 from typing import Union, List, Iterable, Tuple, Dict, Optional
 
 import numpy as np
@@ -45,6 +47,10 @@ class DataHandlerSingleStation(AbstractDataHandler):
     DEFAULT_INTERPOLATION_LIMIT = 0
     DEFAULT_INTERPOLATION_METHOD = "linear"
 
+    _hash = ["station", "statistics_per_var", "data_origin", "station_type", "network", "sampling", "target_dim",
+             "target_var", "time_dim", "iter_dim", "window_dim", "window_history_size", "window_history_offset",
+             "window_lead_time", "interpolation_limit", "interpolation_method"]
+
     def __init__(self, station, data_path, statistics_per_var, station_type=DEFAULT_STATION_TYPE,
                  network=DEFAULT_NETWORK, sampling: Union[str, Tuple[str]] = DEFAULT_SAMPLING,
                  target_dim=DEFAULT_TARGET_DIM, target_var=DEFAULT_TARGET_VAR, time_dim=DEFAULT_TIME_DIM,
@@ -54,10 +60,16 @@ class DataHandlerSingleStation(AbstractDataHandler):
                  interpolation_limit: Union[int, Tuple[int]] = DEFAULT_INTERPOLATION_LIMIT,
                  interpolation_method: Union[str, Tuple[str]] = DEFAULT_INTERPOLATION_METHOD,
                  overwrite_local_data: bool = False, transformation=None, store_data_locally: bool = True,
-                 min_length: int = 0, start=None, end=None, variables=None, data_origin: Dict = None, **kwargs):
+                 min_length: int = 0, start=None, end=None, variables=None, data_origin: Dict = None,
+                 lazy_preprocessing: bool = False, **kwargs):
         super().__init__()
         self.station = helpers.to_list(station)
         self.path = self.setup_data_path(data_path, sampling)
+        self.lazy = lazy_preprocessing
+        self.lazy_path = None
+        if self.lazy is True:
+            self.lazy_path = os.path.join(data_path, "lazy_data", self.__class__.__name__)
+            check_path_and_create(self.lazy_path)
         self.statistics_per_var = statistics_per_var
         self.data_origin = data_origin
         self.do_transformation = transformation is not None
@@ -215,15 +227,46 @@ class DataHandlerSingleStation(AbstractDataHandler):
         """
         Setup samples. This method prepares and creates samples X, and labels Y.
         """
+        if self.lazy is False:
+            self.make_input_target()
+        else:
+            self.load_lazy()
+            self.store_lazy()
+        if self.do_transformation is True:
+            self.call_transform()
+        self.make_samples()
+
+    def store_lazy(self):
+        hash = self._get_hash()
+        filename = os.path.join(self.lazy_path, hash + ".pickle")
+        if not os.path.exists(filename):
+            dill.dump(self._create_lazy_data(), file=open(filename, "wb"))
+
+    def _create_lazy_data(self):
+        return [self._data, self.meta, self.input_data, self.target_data]
+
+    def load_lazy(self):
+        hash = self._get_hash()
+        filename = os.path.join(self.lazy_path, hash + ".pickle")
+        try:
+            with open(filename, "rb") as pickle_file:
+                lazy_data = dill.load(pickle_file)
+            self._extract_lazy(lazy_data)
+        except FileNotFoundError:
+            self.make_input_target()
+
+    def _extract_lazy(self, lazy_data):
+        _data, self.meta, _input_data, _target_data = lazy_data
+        f_prep = partial(self._slice_prep, start=self.start, end=self.end)
+        self._data, self.input_data, self.target_data = list(map(f_prep, [_data, _input_data, _target_data]))
+
+    def make_input_target(self):
         data, self.meta = self.load_data(self.path, self.station, self.statistics_per_var, self.sampling,
                                          self.station_type, self.network, self.store_data_locally, self.data_origin,
                                          self.start, self.end)
         self._data = self.interpolate(data, dim=self.time_dim, method=self.interpolation_method,
                                       limit=self.interpolation_limit)
         self.set_inputs_and_targets()
-        if self.do_transformation is True:
-            self.call_transform()
-        self.make_samples()
 
     def set_inputs_and_targets(self):
         inputs = self._data.sel({self.target_dim: helpers.to_list(self.variables)})
@@ -658,6 +701,13 @@ class DataHandlerSingleStation(AbstractDataHandler):
         return self.transform(data, dim=dim, opts=self._transformation[pos], inverse=inverse,
                               transformation_dim=self.target_dim)
 
+    def _hash_list(self):
+        return sorted(list(set(self._hash)))
+
+    def _get_hash(self):
+        hash = "".join([str(self.__getattribute__(e)) for e in self._hash_list()]).encode()
+        return hashlib.md5(hash).hexdigest()
+
 
 if __name__ == "__main__":
     # dp = AbstractDataPrep('data/', 'dummy', 'DEBW107', ['o3', 'temp'], statistics_per_var={'o3': 'dma8eu', 'temp': 'maximum'})
diff --git a/mlair/data_handler/default_data_handler.py b/mlair/data_handler/default_data_handler.py
index ddf276cf2d88c108d8622c507471f989c4f99e8b..07a866aec1efd43de42f918844abeb7c3bbc9524 100644
--- a/mlair/data_handler/default_data_handler.py
+++ b/mlair/data_handler/default_data_handler.py
@@ -8,6 +8,7 @@ import gc
 import logging
 import os
 import pickle
+import dill
 import shutil
 from functools import reduce
 from typing import Tuple, Union, List
@@ -86,7 +87,7 @@ class DefaultDataHandler(AbstractDataHandler):
             data = {"X": self._X, "Y": self._Y, "X_extreme": self._X_extreme, "Y_extreme": self._Y_extreme}
             data = self._force_dask_computation(data)
             with open(self._save_file, "wb") as f:
-                pickle.dump(data, f)
+                dill.dump(data, f)
             logging.debug(f"save pickle data to {self._save_file}")
             self._reset_data()
 
@@ -101,7 +102,7 @@ class DefaultDataHandler(AbstractDataHandler):
     def _load(self):
         try:
             with open(self._save_file, "rb") as f:
-                data = pickle.load(f)
+                data = dill.load(f)
             logging.debug(f"load pickle data from {self._save_file}")
             self._X, self._Y = data["X"], data["Y"]
             self._X_extreme, self._Y_extreme = data["X_extreme"], data["Y_extreme"]
diff --git a/mlair/data_handler/iterator.py b/mlair/data_handler/iterator.py
index 30c45417a64e949b0c0535a96a20c933641fdcbb..564bf3bfd6e4f5b814c9d090733cfbfbf26a850b 100644
--- a/mlair/data_handler/iterator.py
+++ b/mlair/data_handler/iterator.py
@@ -9,6 +9,7 @@ import math
 import os
 import shutil
 import pickle
+import dill
 from typing import Tuple, List
 
 
@@ -109,7 +110,7 @@ class KerasIterator(keras.utils.Sequence):
         """Load pickle data from disk."""
         file = self._path % index
         with open(file, "rb") as f:
-            data = pickle.load(f)
+            data = dill.load(f)
         return data["X"], data["Y"]
 
     @staticmethod
@@ -167,7 +168,7 @@ class KerasIterator(keras.utils.Sequence):
         data = {"X": X, "Y": Y}
         file = self._path % index
         with open(file, "wb") as f:
-            pickle.dump(data, f)
+            dill.dump(data, f)
 
     def _get_number_of_mini_batches(self, number_of_samples: int) -> int:
         """Return number of mini batches as the floored ration of number of samples to batch size."""
diff --git a/mlair/model_modules/abstract_model_class.py b/mlair/model_modules/abstract_model_class.py
index 894ff7ac4e787a8b31f75ff932f60bec8c561094..989f4578f78e6566dfca5a63f671ced8120491d8 100644
--- a/mlair/model_modules/abstract_model_class.py
+++ b/mlair/model_modules/abstract_model_class.py
@@ -82,7 +82,7 @@ class AbstractModelClass(ABC):
         self.__custom_objects = value
 
     @property
-    def compile_options(self) -> Callable:
+    def compile_options(self) -> Dict:
         """
         The compile options property allows the user to use all keras.compile() arguments. They can ether be passed as
         dictionary (1), as attribute, without setting compile_options (2) or as mixture (partly defined as instance
@@ -116,7 +116,7 @@ class AbstractModelClass(ABC):
             def set_compile_options(self):
                 self.optimizer = keras.optimizers.SGD()
                 self.loss = keras.losses.mean_squared_error
-                self.compile_options = {"optimizer" = keras.optimizers.Adam(), "metrics": ["mse", "mae"]}
+                self.compile_options = {"optimizer": keras.optimizers.Adam(), "metrics": ["mse", "mae"]}
 
         Note:
         * As long as the attribute and the dict value have exactly the same values, the setter method will not raise
diff --git a/mlair/model_modules/fully_connected_networks.py b/mlair/model_modules/fully_connected_networks.py
index 007b8f0de9d2ea6ad6ae64179371a98a56d40447..9fb08cdf6efacab12c2828ed221966586bce1d08 100644
--- a/mlair/model_modules/fully_connected_networks.py
+++ b/mlair/model_modules/fully_connected_networks.py
@@ -10,53 +10,6 @@ from mlair.model_modules.loss import var_loss, custom_loss
 import keras
 
 
-class FCN_64_32_16(AbstractModelClass):
-    """
-    A customised model 4 Dense layers (64, 32, 16, window_lead_time), where the last layer is the output layer depending
-    on the window_lead_time parameter.
-    """
-
-    def __init__(self, input_shape: list, output_shape: list):
-        """
-        Sets model and loss depending on the given arguments.
-
-        :param input_shape: list of input shapes (expect len=1 with shape=(window_hist, station, variables))
-        :param output_shape: list of output shapes (expect len=1 with shape=(window_forecast))
-        """
-
-        assert len(input_shape) == 1
-        assert len(output_shape) == 1
-        super().__init__(input_shape[0], output_shape[0])
-
-        # settings
-        self.activation = keras.layers.PReLU
-
-        # apply to model
-        self.set_model()
-        self.set_compile_options()
-        self.set_custom_objects(loss=self.compile_options['loss'])
-
-    def set_model(self):
-        """
-        Build the model.
-        """
-        x_input = keras.layers.Input(shape=self._input_shape)
-        x_in = keras.layers.Flatten()(x_input)
-        x_in = keras.layers.Dense(64, name="Dense_64")(x_in)
-        x_in = self.activation()(x_in)
-        x_in = keras.layers.Dense(32, name="Dense_32")(x_in)
-        x_in = self.activation()(x_in)
-        x_in = keras.layers.Dense(16, name="Dense_16")(x_in)
-        x_in = self.activation()(x_in)
-        x_in = keras.layers.Dense(self._output_shape, name="Dense_output")(x_in)
-        out_main = self.activation()(x_in)
-        self.model = keras.Model(inputs=x_input, outputs=[out_main])
-
-    def set_compile_options(self):
-        self.optimizer = keras.optimizers.adam(lr=1e-2)
-        self.compile_options = {"loss": [keras.losses.mean_squared_error], "metrics": ["mse", "mae"]}
-
-
 class FCN(AbstractModelClass):
     """
     A customisable fully connected network (64, 32, 16, window_lead_time), where the last layer is the output layer depending
@@ -66,11 +19,15 @@ class FCN(AbstractModelClass):
     _activation = {"relu": keras.layers.ReLU, "tanh": partial(keras.layers.Activation, "tanh"),
                    "sigmoid": partial(keras.layers.Activation, "sigmoid"),
                    "linear": partial(keras.layers.Activation, "linear"),
-                   "selu": partial(keras.layers.Activation, "selu")}
-    _initializer = {"selu": keras.initializers.lecun_normal()}
+                   "selu": partial(keras.layers.Activation, "selu"),
+                   "prelu": partial(keras.layers.PReLU, alpha_initializer=keras.initializers.constant(value=0.25))}
+    _initializer = {"tanh": "glorot_uniform", "sigmoid": "glorot_uniform", "linear": "glorot_uniform",
+                    "relu": keras.initializers.he_normal(), "selu": keras.initializers.lecun_normal(),
+                    "prelu": keras.initializers.he_normal()}
     _optimizer = {"adam": keras.optimizers.adam, "sgd": keras.optimizers.SGD}
     _regularizer = {"l1": keras.regularizers.l1, "l2": keras.regularizers.l2, "l1_l2": keras.regularizers.l1_l2}
     _requirements = ["lr", "beta_1", "beta_2", "epsilon", "decay", "amsgrad", "momentum", "nesterov", "l1", "l2"]
+    _dropout = {"selu": keras.layers.AlphaDropout}
 
     def __init__(self, input_shape: list, output_shape: list, activation="relu", activation_output="linear",
                  optimizer="adam", n_layer=1, n_hidden=10, regularizer=None, dropout=None, layer_configuration=None,
@@ -96,12 +53,12 @@ class FCN(AbstractModelClass):
         self._update_model_name()
         self.kernel_initializer = self._initializer.get(activation, "glorot_uniform")
         self.kernel_regularizer = self._set_regularizer(regularizer, **kwargs)
-        self.dropout = self._set_dropout(dropout)
+        self.dropout, self.dropout_rate = self._set_dropout(activation, dropout)
 
         # apply to model
         self.set_model()
         self.set_compile_options()
-        self.set_custom_objects(loss=custom_loss([keras.losses.mean_squared_error, var_loss]), var_loss=var_loss)
+        self.set_custom_objects(loss=self.compile_options["loss"][0], var_loss=var_loss)
 
     def _set_activation(self, activation):
         try:
@@ -139,12 +96,11 @@ class FCN(AbstractModelClass):
         except KeyError:
             raise AttributeError(f"Given regularizer {regularizer} is not supported in this model class.")
 
-    @staticmethod
-    def _set_dropout(dropout):
-        if dropout is None:
-            return dropout
-        assert 0 <= dropout < 1
-        return dropout
+    def _set_dropout(self, activation, dropout_rate):
+        if dropout_rate is None:
+            return None, None
+        assert 0 <= dropout_rate < 1
+        return self._dropout.get(activation, keras.layers.Dropout), dropout_rate
 
     def _update_model_name(self):
         n_input = str(reduce(lambda x, y: x * y, self._input_shape))
@@ -168,7 +124,7 @@ class FCN(AbstractModelClass):
                                           kernel_regularizer=self.kernel_regularizer)(x_in)
                 x_in = self.activation(name=f"{self.activation_name}_{layer + 1}")(x_in)
                 if self.dropout is not None:
-                    x_in = keras.layers.Dropout(self.dropout)(x_in)
+                    x_in = self.dropout(self.dropout_rate)(x_in)
         else:
             assert isinstance(self.layer_configuration, list) is True
             for layer, n_hidden in enumerate(self.layer_configuration):
@@ -176,7 +132,7 @@ class FCN(AbstractModelClass):
                                           kernel_regularizer=self.kernel_regularizer)(x_in)
                 x_in = self.activation(name=f"{self.activation_name}_{layer + 1}")(x_in)
                 if self.dropout is not None:
-                    x_in = keras.layers.Dropout(self.dropout)(x_in)
+                    x_in = self.dropout(self.dropout_rate)(x_in)
         x_in = keras.layers.Dense(self._output_shape)(x_in)
         out = self.activation_output(name=f"{self.activation_output_name}_output")(x_in)
         self.model = keras.Model(inputs=x_input, outputs=[out])
@@ -184,3 +140,30 @@ class FCN(AbstractModelClass):
     def set_compile_options(self):
         self.compile_options = {"loss": [custom_loss([keras.losses.mean_squared_error, var_loss])],
                                 "metrics": ["mse", "mae", var_loss]}
+
+
+class FCN_64_32_16(FCN):
+    """
+    A customised model 4 Dense layers (64, 32, 16, window_lead_time), where the last layer is the output layer depending
+    on the window_lead_time parameter.
+    """
+
+    _requirements = ["lr", "beta_1", "beta_2", "epsilon", "decay", "amsgrad"]
+
+    def __init__(self, input_shape: list, output_shape: list, **kwargs):
+        """
+        Sets model and loss depending on the given arguments.
+
+        :param input_shape: list of input shapes (expect len=1 with shape=(window_hist, station, variables))
+        :param output_shape: list of output shapes (expect len=1 with shape=(window_forecast))
+        """
+        lr = kwargs.pop("lr", 1e-2)
+        super().__init__(input_shape, output_shape, activation="prelu", activation_output="linear",
+                         layer_configuration=[64, 32, 16], optimizer="adam", lr=lr, **kwargs)
+
+    def set_compile_options(self):
+        self.compile_options = {"loss": [keras.losses.mean_squared_error], "metrics": ["mse", "mae"]}
+
+    def _update_model_name(self):
+        self.model_name = "FCN"
+        super()._update_model_name()
diff --git a/requirements.txt b/requirements.txt
index 51d6e0233c514f15b4724309874ff746234c3b75..85655e237f8e10e98f77c379be6acd0a7bb65d46 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,6 +10,7 @@ chardet==4.0.0
 coverage==5.4
 cycler==0.10.0
 dask==2021.2.0
+dill==0.3.3
 fsspec==0.8.5
 gast==0.4.0
 grpcio==1.35.0
diff --git a/requirements_gpu.txt b/requirements_gpu.txt
index 11a5c8aeedf513b0f0b2373a4ef992d8d2ec28c7..cc189496bdf4e1e1ee86902a1953c2058d58c8e4 100644
--- a/requirements_gpu.txt
+++ b/requirements_gpu.txt
@@ -10,6 +10,7 @@ chardet==4.0.0
 coverage==5.4
 cycler==0.10.0
 dask==2021.2.0
+dill==0.3.3
 fsspec==0.8.5
 gast==0.4.0
 grpcio==1.35.0
diff --git a/test/test_data_handler/test_data_handler_mixed_sampling.py b/test/test_data_handler/test_data_handler_mixed_sampling.py
index d2f9ce00224a61815c89e44b7c37a667d239b2f5..2a6553b7f495bb4eb8aeddf7c39f2f2517edc967 100644
--- a/test/test_data_handler/test_data_handler_mixed_sampling.py
+++ b/test/test_data_handler/test_data_handler_mixed_sampling.py
@@ -37,7 +37,7 @@ class TestDataHandlerMixedSamplingSingleStation:
         req = object.__new__(DataHandlerSingleStation)
         assert sorted(obj._requirements) == sorted(remove_items(req.requirements(), "station"))
 
-    @mock.patch("mlair.data_handler.data_handler_mixed_sampling.DataHandlerMixedSamplingSingleStation.setup_samples")
+    @mock.patch("mlair.data_handler.data_handler_single_station.DataHandlerSingleStation.setup_samples")
     def test_init(self, mock_super_init):
         obj = DataHandlerMixedSamplingSingleStation("first_arg", "second", {}, test=23, sampling="hourly",
                                                     interpolation_limit=(1, 10))