I had no clue what he might be talking about, but now that you mention
it...maybe it is hornwort. He said "semi-floating," and hornwort is the only
common plant I know of that's semi-floating. Most either float or don't. g

OTOH, hornwort doesn't generally do well in very warm water, so temperature
does bother it.



Leigh

http://www.fortunecity.com/lavender/halloween/881/