+1 to lilnau. ^
Your plants seem to be slow-med growing. How about anarachis, duckweed, hornwort, and water wisteria? Oh, gosh.. I like floaters too much. lol I hope your Fluval has bright light? The plants above love their light.
Beware of the hornwort and anarachis, the hornwort will melt in warm tanks without acclimation and so will anarachis. Anarachis will melt sometimes, but they'll come back in a few weeks time.
EDIT: Same timing. hehehe ^.^
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