Hello..
Ecosystem :- a community of organism interacting with each other plus the environment in which they live and with which they also interact is called an ecosystem.
- the example of ecosystem are:-
1- A forest
2- A sea
3- A desert
4- A mountain.
- All the above ecosystem are made up of two main components :-
(1)- abiotic components :- these include physical environment, inorganic substances and climatic factors.
(2)- biotic components these include all plants and animals which may be any of the following type i.e all producer organism ,consumer organism or decomposer organisms.
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- There is a need to clean the aquarium but not to clean the pond and lakes because Ponds,etc are self sustained ecosystem in which the decomposers are active. While the aquarium is not a self sustained ecosystem ,it is an artificial ecosystem so there is a great need to clean the aquarium.
HOPE THIS HELPS!!