Underwater fixtures are designed for use below the water surface in ponds, fountains, pools, or marine environments. These fixtures aid in the safety, visibility, and visual appeal of water features at night. Underwater lights also help to attract fish, as they draw in plankton and small baitfish. In low-light conditions and murky water, underwater lights enhance visibility for ships and boats. They are installed on the surface, through a drilled hole, or attached using trim tabs on boats. This allows flexibility in placement depending on the boat’s design and lighting needs. Pools, waterfalls, spas, docks, koi ponds, aquariums, and architectural fountains utilize these lights for an ambience. What are the Key Features of Underwater Lights? Feature Description Purpose Provides illumination for ponds, fountains, pools, and other water features to enhance aesthetics and visibility. Mounting Style Submersible fixtures placed on the bottom, sides, or integrated into fountains and pool walls. Light Direction Can be focused (spotlights) or diffused (floodlights) to highlight underwater features, plants, or fish. Light Source Primarily LED for energy efficiency, color options, and long life; some halogen models still available. Design Compact, sealed housings made to operate underwater; available in single-color, RGB, or color-changing designs. Durability Constructed with corrosion-resistant materials such as stainless steel, brass, or heavy-duty plastic. Power Source Low-voltage (12V/24V) wiring for safety, with some solar-powered options for smaller water features. Waterproof Rating Typically IP68, ensuring continuous submersion protection in water. Installation Placed directly in water with weighted bases, mounted on walls, or integrated into pool/fountain structures. Applications Used in swimming pools, ponds, fountains, waterfalls, aquariums, and decorative water features for ambiance and safety. Table of Contents What Materials Are Underwater Lights Made Of? Underwater lights are made up of these four materials: Marine-Grade Stainless Steel: Stainless steel offers maximum corrosion resistance in marine environments. 316 stainless steel carries molybdenum, unlike 304 stainless steel. This molybdenum enhances resistance to pitting and crevice corrosion caused by saltwater. The marine-grade stainless steel also contains chromium, which forms a chromium oxide layer, enhancing the durability and impact resistance. The IP-68-rated lights are preferred for use underwater for their waterproof nature. Marine-grade stainless steel lasts for more than 50 years. Brass/Bronze: Both brass and bronze are known for their long lifespan. Brass contains copper, which forms a patina blue-green layer when it reacts with air and moisture. This tarnish layer prevents corrosion of brass, thus increasing its lifespan. But this layer changes the color of the brass. Brass is able to endure 400°F temperatures, which makes it a practical choice for low-temperature regions. Bronze is resistant to corrosion, and it endures temperatures in the range of -450°F to 1200°F. This feature makes it an ideal choice for high-temperature water. It usually lasts 1000+ years underwater. Plastic or Composite Resin: ABS plastic and fiberglass-reinforced plastic(FRP) are widely used in underwater lights. ABS plastic is resistant to wear, chemicals, and impact, which makes it ideal for swimming pool lights. FRP combines glass fiber and plastic resin for strength and moldability. It is more robust and resistant to impact than normal plastic, e.g, polycarbonate and acrylic. The incorporation of carbon black, zinc oxide(ZnO), and titanium dioxide(TiO2) into the composites increases their UV resistance. Tempered Glass: The tempered glass manufacturing process involves heating the glass, which forms a layer of compressive stress on it. This layer aids in its strength and resistance to harsh weather. The tempered glass withstands temperatures ranging from -70 °C to 300 °C, making it a suitable choice for an underwater environment. It transmits clear and bright lights, which enhances the ambiance of the water. It shattered into blunt pieces on breakage instead of large, sharp shards. What are the Types of Underwater Lights? There are five types of underwater lights: Submersible Spotlights: These fixtures are used to highlight specific underwater objects. These fixtures are designed with stainless steel for enhanced durability. Submersible spotlights are constructed with weatherproof, robust housing to ensure safety underwater. They are rated for underwater use, like IP-67/68 are preferred for use in water. Modern submersible fixtures utilize LED technology for 50,000+ hours of lifespan. The low-voltage use (up to 12V) is recommended to maintain safety in water. Pool Lights: The pool lights are used to illuminate the pool areas for enhanced safety at night. They come in various types: surface-mounted, underwater, and floating options. The color-changing feature of these lights gives a cozy feel. Modern lights offer smart functions, like turning lights on/off automatically or changing the colors after a specific time period using a remote or an app. Fountain Lights: These lights are used to enhance the aesthetic appeal of fountains or waterfalls. The ring or nozzle-mounted fountain lights are used for synchronized lighting effects. They come in various styles, including warm white or color-changing options. Hard-chrome-plated or stainless material increases its lifespan to 50+ years. Pond Lights: Freestanding or stake-mounted lights used to enhance the natural ponds and waterfalls’ aesthetic appeal. LED lights are mostly preferred due to their high energy efficiency and color-changing effects. Solar lights are low in cost and environmentally friendly, especially for smaller ponds nd the areas where wiring is difficult. Dock or Boat Lights: Boat fixtures are designed for underwater marine use in lakes, harbors, or on vessels. They illuminate the boat during docking maneuvers, which helps boaters to see the slip, dock, or any other obstacle. These lights are usually attached on the boat itself. What are the Power Source Options for Underwater Lights? Here are the six power source options for underwater lights: Low Voltage (12V): The low-voltage power source is generally preferred for underwater use. It is highly energy efficient and safe, but needs a separate transformer for installation. It is ideal for residential applications, like swimming pools and fountains. Line Voltage (120V/230V): The line voltage connects directly with the main power source. The deep-water installations require a consistent power source, as it is difficult to change the power source occasionally. The line voltage offers a stable system for long-term use. Since this system