I lived in Florence, SC, for eight years, up until a year and a half ago when I moved to Savannah.
Pet World on Cashua is not recommended. I went there several times, and the owner was very off-putting. He would talk down to you as if you were a child, and he was not at all knowledgeable about planted aquariums. On the plus side, most of his fish seemed healthy. I am told he was big into breeding angelfish, but I don't know if that was true. Regardless, I never gave him any of my money as he seemed neither intelligent nor honest.
Pet Lovers on Irby is an okay store for tropical fish, with a decent selection of fish and a small selection of plants. The reason I gave my business to Pet Lovers, however, was because of one of their employees. A man named Gregg who works there is very knowledgeable about both fish and planted aquariums. He was always friendly, honest, and willing to order anything they didn't have in stock (fish, plants, whatever). The fish I bought there were always very healthy and I never had any issues. Bought some Crypts there as well and they did quite good in my aquarium.
PetSmart is the only other game in town, and they are your standard big box pet store.