How to Remove Barnacle Build-Up from Underwater Fishing Lights

It doesn't matter what it is - a boat, piece of rope, piling, hidden treasure, or underwater fishing lights - barnacles are bound to cling to it before long. 

There are things you can do to minimize barnacle build-up such as running your lights for longer durations, pulling the lights up when they are not in use, using barnacle resistant paint, and more but we won't dive too deep into those methods. All of these methods are capable of increasing barnacle resistance, but none of them will totally eliminate barnacles. 

Barnacles are made up of nearly 97% calcium carbonate by weight and 3% organics, per the National Center for Biotechnology Information.

Keeping this in mind, we need something that will break down the calcium deposits. If you have a tankless hot water heater and you have hard water, you may already know where we're going with this. The best way to flush a fouling tankless hot water heater is with white vinegar - the same will be the case for removing barnacle build up on underwater fishing lights. Let's get started!

Materials Needed for Barnacle Removal

1. 5 Gallon Bucket

2. 2x 1 Gallon Jugs of White Vinegar 

3. Flathead Screw Driver

You probably have a 5 gallon bucket and a flathead screw driver laying around the house, 1 gallon jugs of white vinegar can typically be found at your local grocery store. We purchased ours from Wal-Mart - they are pretty cheap (we paid $3.34/gal) as shown in the photo below. 

How to Remove Barnacle Build Up

Step 1

Dispense both 1 gallon jugs of white vinegar into the 5 gallon bucket.

Note: You may need more white vinegar than this depending on the size of your underwater fishing light, or whatever part you are cleaning. We have found that most underwater fishing lights can be fully submerged with 2 gallons of white vinegar in a 5 gallon bucket. 

Step 2

Place the barnacle-encrusted light (or part) into the bucket filled with white vinegar. 

Note: The barnacles should be fully submerged in the white vinegar. If they are not submerged, then add more white vinegar. 

Step 3

Wait at least 20-30 minutes to allow the white vinegar to break down the calcium deposits. The longer you wait, the easier it will be to remove the barnacle build up. 

Step 4

Remove the underwater light (or part) that has barnacle build-up on it and use the flat head screwdriver to scrape the barnacle build up off the light. The barnacles should come off relatively easily. 

Note: If the barnacles will not come off easily, then re-submerge the light in white vinegar and repeat step 3 until you are able to remove the barnacle build up. 

Step 5

Once light is clean of barnacles, you're finished! 

How to Prevent Barnacles from Coming Back

Unfortunately, barnacles are inevitable to occur on anything that stays underwater.   The National Center for Biotechnology Information says it takes as little as 48 hours for barnacles to mineralize their exoskeleton (onto a fixture underwater). That basically means in as little as 2 days, you can have full barnacle growth on your lights. In as little as 16 hours, you can have a white calcium deposit which represents the beginning of a barnacle growth. In as little as 5-6 hours, a barnacle organism could have already latched onto your light fixture. 

Here are some methods that can help slow down your barnacle build up. 

Anti-fouling barnacle resistant paint - this can help reduce barnacle build-up for a short term. These paints slowly release a poison into the water, which deters barnacle growth for a short duration but can also impact other marine life and marine ecosystem.

Some paints claim to last for 3-4 months while others claim to last for 6 months to a year. In our experience, even with these paints, barnacle growth will still occur it will just be delayed. 

Removing Light from Water when not using - this is the only tried and true method to preventing barnacle build up. Don't give them the chance to latch on by leaving it in the water for long durations. 

At the end of the day, concentrated heat can also help deter barnacle growth. The problem is that everywhere else on the fixture that doesn't receive that concentrated heat will still get barnacle build up. Eventually, the barnacles will overcome the fixture and cause it to burn out whether it's a housing-protected underwater light or an exposed bulb underwater light. So a big part in having underwater fishing lights is accepting the responsibility that there will be maintenance involved.

Otherwise, if you want something maintenance free, we recommend you consider an above water fishing light.