8 Systemic fertilizers The sera systemic fertilizers close specific maintenance gaps. For the tailor-made supply even of very fastidious aquarium plants. The alternative carbon source sera flore 1 carbo Carbon deficiency is likely the most common growth limiting factor for aquatic plants. sera flore 1 carbo, a liquid fertilizer with car- bon sources easily accessible for plants, pro- vides an uncomplicated, reasonably priced alternative or addition to the CO2 fertilization system. Application: daily fertilizer for the growth sup- porting carbon supply