Sera 275R/550R Replacement Diaphragm Module (06732) for sera air 275 R plus for sera air 550 R plus   Complete replacement kit for sera air 275 R plus and 550 R plus (2 spare modules are required for 550 R plus).

Sera CO2 Start (08039) For a start into CO2 fertilization Carbon dioxide (CO2) is the basic plant nutrient and allows adjusting a slightly acidic pH value, as it is preferred by many plants and fish. The sera CO2-Start fertilizer system is easy to...