Red or very quickly growing aquatic plants require particularly much iron. Iron deficiency therefore often occurs in densely planted and intensely lighted aquariums. The aquatic plants, however, require iron for developing their full color splendor and for growing healthily. The new systemic plant care sera flore 2 ferro was developed specially for this case. It provides sufficient iron for the plants and therefore supports color development. UV-C water clarifiers, which quickly damage normal iron complexes, are used in many aquariums. Iron is then available in a form that can be taken up by plants only for a very while. This is not the case with sera flore 2 ferro. Using specially chelated iron allows for long availability of several days. sera flore 2 ferro does not contain any nitrate nor phosphate. It is well tolerated by all invertebrates.