If your considering underwater lighting for your boat or dock then there are a few things you want to know first so that you can be sure to get the correct lighting system and understand what it requires to keep the lights working.
The switch to LED lighting is fast growing in the marine industry. With the tech now available you can get some really good light output from considerably lower amps now as opposed to what was available only a few years back. I'm going to concentrate this on underwater led lighting that is primarily used on boats.
To get started we need to determine the type of light we need by first considering how we keep the vessel. Is it kept out of the water on a trailer, lift or storage and placed in the water when we intend on using it? Or is your vessel kept in a slip for long periods of time and the lights kept underwater? This is the most important question regardless of the brand of light you have or intend to buy. It also comes with completely different maintenance routines!!!
First let's start with trailered boats since these are the most common. The maintenance for these lights is minimal. Since fouling is non existent due to the boat being dry dock you will not need to worry about it. However , you will need to understand that there are several other problems that occur and are ultimately the destroyer of your nice (and probably very expensive) lights.
1. Corrosion !!
99% of all lights offered on the market are corrosive and the manufactures state this very clearly in there warranty's. The biggest brands such as Lumitec , Oceanled and shadowcaster all have disclaimers that void your warranty as soon as you install the lights. If your not hip to how metals react with each other and you think that because you paid 100's for the light it will somehow be guarded against corrosion then you are sadly mistaken.
This turns into this 
and later this happens
and I promise you they will not replace them!
If your wondering how to stop the corrosion? You can't! This will happen to 100% of the lights that have anything other than a stainless body or composite body ( our lights have 0 metal exposed so they are corrosion free). The reason this happens is because stainless (the screws) are connected to the body of the light. However the body is an aluminum alloy and stainless actually is a huge thief of electrons from other metals. If you look at Marine boats you will see that if there are metals other than stainless being used in conjunction with stainless there is always an anode in place. Underwater LED lights really don't have the room for anodes and the anode only slows the process. You can use nylon washers to help prevent the corrosion but again. The minerals in the water will cause the same effect. So the best way to maintain a light that has any exposed metal that's not stainless is to not use it or clean it each time it is removed from the water and to keep (corrosion X ) a coat of anti corrosion additive on the lights after removal. This only extends the life of the light , it does not prevent the problem.
2. Using your lights
We all know that it's a pretty awesome sight to be up and running with the lights making the wake light up like flames behind the boat right? It's ok to do this as long as you understand that the lights can only be done this way for short periods (1-2min). If you have high powered LED lights on the transom of the boat then they are probably not in the water when you are up and running on plane. Some boats create enough back splash to help cool the lights but that's very minimal. 100% of all underwater lights use the physics of heat dissipation in water as a factor when building the lights. With that said, running the lights out of water will void the warranty on 100% of all lights offered other than thebestfishinglights TB Series. This is because several things happen depending on the brand and how they are built. Most manufactures use compression gaskets and seals for waterproofing. Very similar to how watches are built. This works great until you apply heat! Just like the stories you hear about how someone took a hot shower with there nice waterproof watch and then all of the sudden they have condensation in the watch? How does this happen? Let's look at what is really going on here. You have a sealed space that has air at normal temperatures with no internal or external pressure. If you heat the air it expands right? (hot shower). Now we all know the watch(light) was designed for external pressure to prevent water from getting in it. What happens when the air expands? That's right, it releases through the seal. Now let's see what happens when the air returns to normal temps? Now there is less air inside the watch(light) so a vacuum is formed. Once again the watch(light) was only designed for external pressure and not an internal vacuum. The end result is the watch equalizes and sucks air/water depending on location back into the space to equalize. So while running high powered LED underwater lights out of water is not only bad for the circuits heat it is a destroyer if you let off the throttle and dump it in the water and instantly cool it. That's a good way to trash 100's in just a few minutes. Our lights are not immune to the same physics. The sudden change in max temp to cool will cause the solid core to cool more rapidly on the exterior and thus create cracks. The Best Fishing Lights TB Series can withstand a lot of abuse but, if things go south and you have a failure don't worry. We will replace them and issue a warning about preventing it in the future.
This pretty much covers the ideas that will help you come up with the best way to care for you lights on a trailered boat. I hope it helps
Tight Lines!!
Kevin Green
