A kind of fish jar not plug-in automatic water changer,Comprising: a water inlet pipe； One the first container,One first bend pipe is vertically planted in bottom,When the water inlet water inlet tube what the first container,When the high what of water level the first bend pipe top,It is drained； One second container,The draining of the first container is accommodated with what,It is partitioned into one first space and a second space,First space bottom vertically plants one second bend pipe,A third bend pipe is vertically planted in the second space bottom,The second bend pipe tip height is identical as the third bend pipe tip height,When the high what of water level this second,When three bend pipe tops,It is drained； One third container,The draining in first space is accommodated with what,The container bottom vertically plants one the 4th bend pipe,When high the 4th bend pipe top of what of water level,It is drained； One fish jar,Bridge a S type bend pipe on one side,The S type bend pipe one end extends downward into the bottom of the fish jar,The other end bridges a drain elbow upwards,When the draining of the second space is to the fish jar,When so that the fish jar water level being promoted to the drain elbow tip height,It is drained,It is down to when the drain elbow bridges and holds height when water level and stops draining,The third container starts to drain at this time,The fish jar water level is promoted to ordinary water level.一種魚缸不插電自動換水裝置，其包括：一進水管；一第一容器，底部垂直插置一第一彎管，當該進水管進水於該第一容器，水位高於該第一彎管頂端時，進行排水；一第二容器，用於容納該第一容器之排水，區隔成一第一空間及一第二空間，該第一空間底部垂直插置一第二彎管，該第二空間底部垂直插置一第三彎管，該第二彎管頂端高度與該第三彎管頂端高度相同，當水位高於該第二、三彎管頂端時，進行排水；一第三容器，用於容納該第一空間之排水，該容器底部垂直插置一第四彎管，當水位高於該第四彎管頂端時，進行排水；一魚缸，一邊跨置一S型彎管，該S型彎管一端向下延伸至該魚缸之底部，另一端向上跨置一排水彎管，當該第二空間之排水至該魚缸，使得該魚缸水位提升至該排水彎管頂端高度時，進行排水，當水位降至該排水彎管跨置端高度時停止排水，此時該第三容器開始排水，將該魚缸水位提升至正常水位。
