Generally, if a hotel has a swimming pool, it will be clean. From my experience, there are only two grades of hotels in India. Nice hotels, which include the luxury kinds. And cheap hotels, which include hostels. Nice ones will have all the amenities you would expect, and would fit well in any Western nation. Cheap ones are on par with Motel 8, or worse. You get what you pay for. But if you stay at a cheap hotel, you probably are not there for a swim. You just want a bed to sleep in so you can have the energy to continue your trip and see more of the beautiful country.