20cm方缸使用集成式背滤，The fish tank has a built-in filter.

20cm方缸使用独立式整体背部过滤器，根据搭配不同过滤盒可以制作海水鱼缸和淡水鱼缸。

The 20cm square tank uses an independent integral back filter. Depending on the combination of different filter boxes, it can be made into a saltwater fish tank or a freshwater fish tank.

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