Underwater Lights: Features, Installation, and Maintenance

What Materials Are Underwater Lights Made Of?

Underwater lights are made up of these four materials:

1. 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.
2. 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. 
3. 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.
4. 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:

1. 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. 
2. 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. 
3. 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. 
4. 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.
5. 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:

1. 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. 
2. 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 operates in connection with the home/port setup, it needs to be installed near them.
3. Solar Powered: The solar-powered fixtures utilize photovoltaic panels p charge during the day and illuminate the area at night. It is limited to use for shallow water and small fountains. Because it lasts for up to 8-10 hours on its full charge, and requires proper sun exposure during the charging period. So, it’s not used in deep water installations, as they require a continuous and strong power source to run efficiently. Solar-powered fixtures are mostly used in isolated areas, where there is no power source. 
4. Battery Operated: These fixtures are suitable for temporary use, as the battery needs to be changed after every 12-24 hours, depending on the battery type. These fixtures are highly portable and recommended for outdoor camping and night events. Puck lights with alkaline batteries last for up to 20-100 hours, while rechargeable lithium-ion batteries last for 100-300 hours. 
5. DMX/Smart Control: Advanced options offer lighting automation or syncing. DMX stands for digital multiplex, which allows control of all the lights using a single controller. These fixtures use a data signal to measure the intensity and control the colors and other parameters. The smart control systems are typically controlled using an app or a voice assistant like Google Assistant or Alexa. The DMX-powered fixtures are highly energy efficient.

How to Choose the Right Underwater Light?

Follow the following six steps to choose a suitable underwtaer lights for your area:

1. Installation Environment: Select fixtures based on pool, pond, or marine use. Marine environments require a tough and saltwater-resistant material like 316 stainless steel. While for pool areas, plastic or bronze material is also considered. 
2. Brightness & Beam Angle: Select the light with the desired brightness and beam angle. Fixtures with a lower lumen output, around 200 to 400 lumens, give fountains and waterfalls a soft, ambient glow. Higher lumen levels, around 800 to 1,200, offer broader illumination, making them ideal for boats or large ponds. A fixture with a 10°–30° beam angle is used for focused highlighting. Prefer a wider beam around 45°–60° for larger areas. 
3. Color Temperature/Effect:  Choose warm white(2700K-3000K) for a cozy and intimate feel, while cool white(5000K-6500K) is ideal for vibrant, brighter scenes. RGB-based fixtures offer a color-changing feature to set the lights’ color according to mood.
4. Fixture Durability: Freshwater fixtures perform better even with standard metals, while saltwater environments require corrosion-resistant options like stainless steel or marine-grade coatings. The suitable material ensures longevity and requires less maintenance.
5. Control Options: Control options offer flexibility based on user needs. A simple manual switch, a convenient remote control, or a smart app enhances the features of lights. For example, setting a timer for automatically changing colors at any event.
6. Safety Standards: Check the box of the fixture for verifying lighting compliance with water and voltage regulations. This protects users from electrical hazards and prevents damage to the system.

What is the Installation Process of Underwater Lights?

The installation process of underwater lighting involves the following six steps:

1. Plan Layout: Decide exactly where the lights need to be set,  whether at deep ends, around fountains, or along pool pathways.
2. Run Wiring Safely: Use waterproof conduit and certified cables to protect against water damage. Prefer neat and hidden routes so that the wiring stays safe and out of sight.
3. Mount Fixtures Securely:  Fix the lights using sturdy brackets, weights, or in-wall mounts. This keeps them stable even with water movement or pool cleaning.
4. Seal All Connections: Prefer watertight gaskets and waterproof junction boxes to prevent leaks. A proper seal protects the system from short circuits and corrosion.
5. Test Illumination: Switch the lights on before sealing the wires to check brightness, beam spread, and angle. Adjust the light angle properly so that the whole area gets an equal amount of light.
6. Connect to Transformer: Ensure a proper voltage force according to the requirements of the light. Add safety breakers for extra protection and reliable performance.

How to Maintain Underwater Lights 

Occasionally, remove the algae, mineral deposits, and biofilm from lenses for clear and bright light. Regularly inspect the fixtures for leaks or signs of wear and tear, especially after winter. In case of LED damage due to water, opt for timely maintenance or replacements if needed. Always try to maintain a balanced pH and salt levels in the pool to reduce corrosion. But in freezing climates, lights need to be removed or require extra protection to prevent damage. Periodically check cable integrity, particularly in areas with flowing water, to ensure safe and reliable operation.