CO2 Music Counter, Do!aqua is a glass CO2 bubble counter allows the amount of added CO2 is to be measured. The CO2 bubble counter is filled with water and the included transparent suction cups on the outside of the aquarium confirmed.
This glass manifold for a external filter is suitable for an aquarium in which fish swim which quiet flow. With its round shape has the Poppy Glass a cute character.
See table below for the type you want.
(filter outflow is available separately: link)