Why Water Drips From an Aquarium Light Hood

The tales of large aquarium fish could be causing splashing that's landing in your light hood.
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Condensation is most likely the reason your aquarium light hood is dripping water, though there may be another issue causing it. Perhaps your aquarium is sitting on an uneven surface. Or, you may not have fitted the light hood correctly.


Condensation happens inside your aquarium, because wherever there is water, there is water evaporating. If your aquarium has an air pump, you’re likely experiencing bubble condensation. Your air pump causes bubbles to break on the surface of the water and splash the aquarium hood. Eventually, condensation builds and dripping occurs. Heat condensation is when warm evaporated water collects on cooler surfaces and returns to its former liquid state. If you’re without an air pump, but still experiencing condensation, heat condensation is the likely culprit.

The Condensation Tray

Condensation trays shield your lighting system from condensation and the dripping that results from it. Most lighting systems come equipped with a condensation tray, but if yours doesn’t, these trays are offered at most pet stores. These trays protect your electrical setup, as well as your ballast. They also keep your fish from jumping out of your tank. Keep these trays clean to prevent algae buildup.


Your fish could be splashing water into the light hood, especially if they’re large in size. Their splash lands on the light hood and then slowly drips back into your tank. So long as you have a condensation tray affixed, this shouldn’t cause any electrical issues.

The Light Hood Isn’t Secure

If your aquarium light hood is leaking down the side of your tank, it’s likely it’s not fitted correctly. This can be very dangerous, especially if your light hood plugs into an electrical outlet. Consult your owner’s manual to ensure proper installation. If the light hood simply won’t install correctly, you may want to consider a different size or brand.

Uneven Surfaces

If your aquarium isn’t on a flat surface, this could cause tipping and leaking. It may appear that the water is dripping from the light hood when it’s really leaking from the sides of the tank. If any part of your aquarium is electrical this can be very dangerous. Use a level tool to ensure that the surface is perfectly balanced. If you find the surface isn’t balanced, move your tank right away.

The Drip Loop

Anytime you use a household outlet, to provide electricity to aquarium equipment, it’s essential to use the drip loop technique. This simple technique could save your life, should a drip ever travel the length of an electrical cord and find itself inside your socket. Simply ensure that your electrical cord drops low, before it travels back up to the outlet. Should water run down the cord, it will land at the lowest point. It won’t be able to run up the cord to reach the socket, thus preventing water from entering your outlet.

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