Common questions and answers about aquarium hoods and lighting

Advice by Jan, keeping fish since 1995

Your professional guide on aquarium hoods and related FAQ - Jan Hvizdak

Brief Description

Many aquariums nowadays are run open topped but there are cases where a tight fitting hood and built in lighting are necessary. Most bought aquariums will come with a hood and lighting but sometimes fish keepers will resort to making their own. This may sound complicated but it isn’t!

Even the smallest of tanks come complete with a hood and some form of basic lighting. Hoods are normally made from wood, plastic or metal, deciding which one is used is purely personal preference.

Why do I need a hood?

Aquarium hoods serve a few purposes. They will reduce the amount of evaporation from the tank water as well as preventing contaminants entering the tank from outside sources. Hoods also act as a base for attaching the lighting equipment to and with built in flaps give access to all areas. If the aquarium is bought as a complete package, the hood will be a perfect fit and will do its job well. If making your own hood, measure carefully to ensure a tight fit.

Should I choose wooden or plastic for my hood?

As mentioned above, this is personal choice. Plastic hoods are very light and easy to adapt if parts need cutting away to fit equipment into the tank. Wooden hoods are often used to match the décor of the room that the tank is situated in, any colour of wood can be used but it must be treated with a waterproofing to prevent the wood from swelling. Condensation trays should also be used with wooden hoods to help prevent any damage from the inside.

Which is the best aquarium hood to use?

Any hood that does its job and fits well is the best. Some of the more expensive hoods are priced purely on their decorative value and not their efficiency. Bear this in mind when looking for a hood for your own tank. I have bought cheap hoods in the past and they were far better than some of the more expensive ones.

Which are the most popular aquarium hoods?

From my own experience of talking to other fish keepers, the plastic hood that just sits on the top of the tank seem to be the most commonly used. They will normally have hinged flaps that run along the front and back of the hood, this allows for ease of feeding the fish and also for tank maintenance. Because they are so light it is also a simple matter to remove the hood completely if required for the larger maintenance tasks.

How do I know which size hood I need?

There is only one way to determine this, measure the aquarium length and sides; this will give you the size of hood that will be advertised with the corresponding measurements. Read up about the hoods that are for sale as in the description it will also tell you the amount of access the hood will allow with the flaps. All good suppliers should have a guide to help you choose. There is a guide in the following article: aqua-fish.net/articles/aquarium-hoods-guide.

Constructing your own hood

It is another option to make your own hood and not that difficult. I prefer to use wood for my own hoods but plastic sheeting can also be used to great effect. Measure your tank carefully and create the sides, front and back using your measurements. The lid should be fixed at the rear bit add a piano hinge or similar to allow you to make a lifting flap at the front. And that is a basic hood, everything is screwed together and the wood is water proofed, if measured correctly it should sit snug on top of the tank. If using plastic then the pieces will need to be fixed together with a suitable aquarium rated sealant.

Can I fit an automatic fish feeder or other equipment with a hood?

Yes you can, in a perfect world the equipment would just slot into place with out altering the hood but it never works out like that. The easy way to do it is to work out where the equipment is going and then simply cut away a portion of the hood to give it room. With a plastic hood this means just cutting out a small area with a hacksaw and if you have a wooden hood, use a small tenon saw.

Can I use an aquarium hood with plants in the tank?

Using a hood with a planted tank indirectly helps the plants as the hood will host the aquarium lighting. With the lighting being as close to the water surface as is safely possible, it will be more efficient in aiding their growth.

Why does my aquarium hood heat up during the day?

The hood will feel warm to the touch as the lighting gives off heat. This is perfectly normal and nothing to worry about. The hoods are designed to withstand normal amounts of heat from the lighting but if it feels like that it is getting too hot, check out for faults in your lighting system.

Can I modify the lighting if I feel it isn’t strong enough?

The lighting can be modified to stronger tubes etc. If you add brighter tubes remember that the ballast that runs your lighting is rated to the same wattage as the tubes. If you use a stringer wattage tube, you must use stronger rated ballast. If you are converting to a longer tube then the tube holders should unscrew from the hood, then it is just a matter of drilling some fresh holes further apart and replace the tube holders there.

Instead of adding lighting to the hood can I use underwater lighting?

Nowadays there are underwater lighting kits available that are very easy to install. Basically you just place the lights at the bottom of the tank or wherever you want them and plug in. Always ensure that they are waterproof lighting systems. These can range from single light kits for a few pounds up to a group of lights that will cost a lot more.

How much lighting do I need for my aquarium?

The golden rule for aquarium lighting is 1-2 watts per gallon of water. This is more crucial with planted tanks; they generally will need 2 watts per gallon.

Work out the water volume of the tank and then just multiply it by 2 to get the most efficient lighting for your aquarium.

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