How many fish can call your pond home depends on the volume of the pond and the fish size. Your pond's filtration system also influences the number of fish that will thrive in a pond. A general rule of thumb is to have 1 inch of fish for every square foot in a pond that's 2 feet deep. Another rule of thumb you can follow is to have one koi fish for every 200 gallons of water or two goldfish for every 200 gallons.

Yes, it is possible to make a fountain without a pump, though it may seem less intuitive and will require a bit more effort to use. In lieu of an electric pump, there are a few options including hand-cranked pumps or sprinkler systems that can work to provide water for a fountain.

Whether a natural pool is worth it depends on several factors because they cost more than traditional pools. Many people opt for natural pools because they enjoy swimming in natural bodies of water such as lakes. Also, if you're environmentally conscious, a natural pool is going to be a much more attractive option than a traditional pool.

Moreover, for people with chemical sensitivities, a natural pool is a great solution since the water doesn’t contain chlorine.

In short, yes, a pond can add to your home’s value. However, whether it adds value will depend on the condition and aesthetic of your pond. Having this feature already built into a yard’s home can be appealing to homebuyers who value its aesthetic and would prefer not to build it themselves. But if it is not kept in good condition, it could turn buyers away.