Hiii.....i am new in this forum

actually i have this problem long time... i dont know what is it....because i am beginner with aquatic plant...

actually what is happen with my plant (pic link below)

[url=http://img138.imageshack.us/my.php?i...9030030zw2.jpg]

[url=http://img138.imageshack.us/my.php?i...9030029zx9.jpg]


u see in my plant leaf there are some like "sawang".

please i need to know what is it...because i have put the alga remover medicine....if it not alga it good...i can just leave it....but if alga how to remove it....
it make me runsing la....

before i forget...i have only small aquarium (23L)....

please help me ...thanks

** sorry link for pic is not work...i will post it later...