What kind of plant is that btw?
I dont think it's an aquatic plant, sadly. If its one from those tubes they sell, its a relative of "lucky" bamboo, and only the roots are submergeable. Theyre more for terrariums, me thinks.
Its a golden-something...maybe? I cant remember the name :(
Try for a plant like java fern, anubias, wisteria or an amazon sword (which needs lots of gravel), all are easy and wont rot in that tank.
Keep an eye on that plant :B (the one on the left), if it starts to melt/rot, take it out.
Noice fish, nice tank...minus the watch <3