One kind having the barrel-shaped filter of carbon-dioxide thinning diffusion, and main system includes the base equipped with filter material, and is equipped with the lid of entery and delivery port and motor, blade. Wherein, which is equipped with the carbon dioxide input port of one with blade perforation, for being connected a bubble counter, connects carbon dioxide (CO2 by bubble counter). Enter the water of aquarium by water inlet, the filtering of filter material through base, and it is refined by introducing carbon dioxide through motor blade and diffusion effect, keep the carbon dioxide of the water for filtering Hou and importing fused, and then keep water quality more limpid, and the photosynthesis of sharp what water plant, so that water plant verdant can be more flourished.一種具有二氧化碳細化擴散作用之桶形過濾器，主要係包含設有濾材之機座，以及設有進、出水口及馬達、葉片之蓋體。其中，該蓋體係設有一與葉片貫通之二氧化碳輸入口，以供銜接一計泡器，由計泡器連接二氧化碳(CO2)。使水族箱的水由進水口進入，經機座之濾材的過濾，以及藉由導入二氧化碳經馬達葉片細化及擴散效果，使過濾後的水與導入之二氧化碳溶合，進而使水質更為清澈，以及利於水草之光合作用，使水草更能青翠茂盛生長。
