Welcome to Fountains Aquarium! Come in and visit the oldest Tropical Fish Pet Store in San Diego, California. We have been here to serve all of your Tropical Fish tank and Fish Aquarium San Diego needs since 1950. We specialize in Custom Aquariums plus Freshwater and Saltwater Fish. Aquarium Fish. Aquarium Supplies and lighting as well as Tropical Fish Supplies and equipment. livestock and Ponds and Pond Supplies. We have hundreds of fish tanks with Thousands of exotic freshwater and saltwater fish on display. Open seven days a week. Whether you need a 5 gallon starter tank or a 1000 Gallon Reef Aquarium, we can guide you in the right direction with our experienced staff. We have over 100 years of collective experience.