Possible problems that you may incur:
1)Plant type is not aquatic and will die. See previous post for non-aquatic plants sold as "aquatic." If any of these look like what you have, they will die.
2)You may have purchased plants that required high levels of lighting, co2, ferts, etc... If this is the case, they will not grow, and most likely will die a slow death. This presents two options:
A) You can give up on these plants, do a little research, and purchase low light plants. These plants will grow fine in your tank as is.
B) You can start on an expensive, seemingly never ending journey of upgrading your tank to handle high tech plants. This will
include adding CO2, high levels of light, upgraded substrate, possibly fertilizers, perhaps a new filter, different fish, bigger
tank....the list, at least for me, keeps growing(much like my plants now that I have CO2 and Lighting) I read that you have said
you have "flourescent" lighting. This standard lighthing is not enough. Most likely it is two 15watt bulbs. For your 55, you will need
to pump in at least 110 watts of good 6500k Daylight Bulb lighting in order to be considered "enough" lighting for the high tech
plants. The fixtures you currently have are at most 20 watt fixtures. You won't be able to simply slide in two new 6500k 55 watt
bulbs. You'll have to upgrade the entire fixture.
Point is, going high tech can get very complicated, but, the final product can be very rewarding. However, you can have a very pretty planted tank that is low tech, you just have to pay more attention to your plant selection. If you choose to go high tech, there are many excellent resources throughout this forum. The same applies to low tech. The choice is yours.