could use a little info

[Godfry]

I have had my 60g FWLR tank for about 6 years, and It's been moved 4 times, Everything seems to be doing great. I still have a couple of the original fish when from when I started. But really, I know nothing about this hobby and the things going on in my tank. I just started visiting this site and its raising alot of questions. I use a fluval filter, a prizm skimmer and 55w fluorescent lights. (I clean the fluval 2 times a year if Im lucky). any way I was wondering what a flat worm was because I think I seen one the other day, and how do they negativaly afect your tank? I would like to put some pictures on here but I haven't figured out how to do that yet.