Kiddy pools are all over the place right now and I recently got a Common pleco (no my idea) but he's a problem in my current tank. I can't afford a bigger tank and thought setting up a kiddie pool in my basement (there are EXTREME temperatures outside here) would be a neat idea. I can't use electricity because that would cost a lot of money over time but I do think I could get one if there is no electricity. Would this be possible? I couldn't have lights so that means there would be no plants to oxygenate but I do think I could make a gravity-fed filter without any heaters. I was thinking I could make a filter using how gravel vacuums work or would it stop siphoning eventually? It would just be a goldfish pond with my pleco and nothing that requires heat. Would this be possible and how would I do it? I might need lights so what's the most energy efficient lights out there just in case?