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Our Environment — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceOur Environment3 Marks
Question
We do not clean ponds or lakes, but an aquarium needs to be cleaned. Why?
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Answer

A pond or a lake forms a natural and complete ecosystem. All the food chain presents in these ecosystems are complete. These ecosystems have plenty of producers, consumers and decomposers.
On the other hand an aquarium is an incomplete artificial ecosystem. An aquarium does not have enough population of decomposers to decompose waste material produced by aquatic animals. Due to this reason aquarium needs to be cleaned frequently.

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