Need help to identify plant.

[lyebw225]

I recently bought this floating plant, seems like a frogbit but i'm not too sure. Any one knows?

This is a picture when i first bought it.
https://www.dropbox.com/sc/q59sp8yny7cklev/LYSu8Q9Tp6

But over a week, some of the leaves have turned brown. Not sure if it's because some leaves are submerged in the water. Need advice on it. LFS owner told me it doesn't require that much light apparently.
https://www.dropbox.com/sc/cxo0n0isd8vxsnn/vQX_bXpu6Y

[seudzar]

Nope... Definitely not frogbit..

[Shifty]

That looks like a water hyacinth commonly found floating in ponds. It does get massive and spreads like a weed. not sure about the browning but my guess would probably be due to insufficient lights/nutrients.

[lyebw225]

i see...so water hyacinth is harder to manage than frogbit? it has long roots so i mistaken it for frogbit. for now, the leaves that are submerged are the ones with the most browning. anyone has more knowledge on this water hyacinth? do i need really strong light and fertilizers?