According to Tropica Plants, Ceratophyllum Demersum exhibits "alleopathic behaviour". That is, it excretes substances that inhibit algae growth. Does anyone know if other plants do this? Do these substances also inhibit general plant growth or is the effect limited to algae? It seems that if this is true, then algae control could at least be given a boost by using bunches of plants that exhibit alleopathic behavior. Any thoughts? Kind Regards, Justin