Do you really want Petco, that knows nothing about fish and planted tanks(dog and cat care isn't that difficult), to educate you on something? I can see if it is an aquarium store. It is a petshop, most employees aren't hobbyists and need money. At a store that specializes in aquariums, like the one by me (Neptune Aquatics), they are all hobbyists and I doubt you would even be able to work there if you weren't a hobbyist.
I always look and see what people say about something and what it needs. Would you go in and buy a dog with no knowledge expecting someone to tell you everything? You need to really do you're own research because they can also be biased.
15 Gallon NPT
1g no tech bowl in the making