Keep in mind that the retail store is not there just to give you information. There is always the bottom line involved. Everything is not free and so too with the rent. Keep this in mind and always research before you go in. If you have an idea of what you are looking for the store can be a much better resource. Afterall you do not go in and buy a new car without doing a little research first... Once you have some research on what you are looking for go in and discuss it with a store employee. You will be able to quickly tell if they are trying to just sell you as big of a tank as they carry and the most expensive fish they have or if they are trying to guide you on the road to happy fish ownership. If you feel confident in the knowledge of the employee then trust their guidance. If not listen but do not monopolize their time. Stop back another time to ask other employees for information. Visit other stores if possible. Always buy from the dealer who gives you the best service.