Welcome to AA. Neat set up for the turtle! I've never really thought about keeping turtles, but my son keeps trying to convince me.
I hope you aren't feeling discouraged by the suggestions about tank size. Unfortunately, pet stores aren't always forthcoming about how big your fish will grow and some species (plecos are definitely one of them) can grow shockingly big, shockingly quickly. They can also be aggressive towards smaller fish, so you end up needing to be careful what you keep them with once they mature.
Poke around the forums, searching for things that interest you. (You can use the search function with keywords like 'turtle' and find other relevant threads.) There's so much info here that it can be overwhelming at times - I know I am still reeling from it all and can get lost here for hours. Plus, people are really helpful and will answer the questions you post, often very quickly.