Heather: Heather is a natural product (8-30 years old) with a coarse woody structure. Heather is cut approx. 30-40 cm above the ground level, after which the growing process can start again, and is consequently a very environmentally friendly product.
Peat fibre: Peat fibre is the coarsest fraction of peat. It has a fibrous, airy structure, making it a suitable filter medium. Peat contains no substances that are harmful to either health or the environment.
Biomix: Biomix is a filter medium comprising a mix of heather and peat fibre (e.g. 70-30%, 80-20%). Oosterbeek can supply biomix in any proportions required as ready-to-use filter medium.