Hornwort floating at the surface?
I have a few questions about a hornwort species whose exact name I unfortunately do know know anymore.
Ceratophyllum demersum (very common) and C. submersum (rather uncommon) are known in the aquarium hobby.
Now I am wondering whether the hornwort will grow roots at all?
Yes it will - growing roots takes place very quickly, and repeatedly if required.
Until now I just let the plants float freely at the water surface (and it does not seem to have caused them any harm).
Hornwort can indeed be added floating freely without any restriction, it will not harm the plants!
However, the other aquarium plants hardly received any light at all.
This is basically the disadvantage with floating plants or those that tend to cover the surface - however, this shadowing may also be desirable, e.g. for fish that prefer less bright light.
Dr. Bodo Schnell