The plant water conditioner sera Phyto med Tremazide contains as an active ingredient highly effective and natural peppermint oil for the treatment of skin worms and gills in fresh and sea water and in the garden pond. There are no synthetic active ingredients such as chlorine substances. Phyto med tremazide has no effect on biological filtration, is particularly well tolerated and does not lead to bacterial pollution of the aquarium water. Therefore, it is unnecessary to adjust the water parameters and subsequent water change.