English name: Rigid Hornwort

German name: Rauhes Hornblatt

Taxonomy

Division: Magnoliophyta

Class: Magnoliopsida

Order: Ceratophyllales

Family: Ceratophyllaceae

Genus: Ceratophyllum

Species: Ceratophyllum demersum

The Rigid Hornwort (Ceratophyllum demersum) is a cosmopolitan, submergent, dicotyledonous macrophyte. It likes a high nutrient level and summer water temperatures of 15-30 °C. It anchors in the sediment without real roots and develops up to 3m long sprouts. It produces a lot of oxygen, so you can see the gas bubbles between their leaves.