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Do you need to cover the top of your fish tank?

So do you actually need a cover the top of your aquarium? Having a cover has several major advantages that make fish keeping much easier.

Aquarium Top Cover Benefits

Perhaps the most important of which is that a top will prevent fish and other aquatic life (such as snails and shrimps) from jumping and/or escaping the tank. Bettas, guppies, swordtails and other fish types can jump from the top of the tank for many reasons, including poor water quality and being bullied by other inhabitants. Needless to say, having a top will prevent your pets from escaping and possibly dying.

In addition to stopping stuff from getting out, a hood will also prevent potentially harmful outside elements from getting in the tank. For example, sprays from air fresheners, cleaning solutions and perfume could unintentionally be added to the tank water in aquariums that have an open top.

Bugs will also get into your tank. Dragonflies and damselflies will lay eggs on your fish tank if you don’t cover it. These eggs, when aren’t eaten by the fish and/or taken out, will develop into nymphs. During this stage, the dragonflies and damselflies will predate on small shrimp and fish in your aquarium. Not to mention that some bugs can also carry diseases and other potential toxins if they get into your tank and eaten by your fish.

Having a fish tank hood will prevent water evaporation as well. If you don’t have a cover, water will evaporate into the air in your room. This makes the water quality in your tank worse as you are losing H20 while your ammonia, nitrite and nitrate stays the same inside your aquarium. Not to mention that the beneficial bacteria you have near the top of your tank will die off by drying out. The evaporated water could also damage the walls in your room and electronics as it raises humidity.

A cover will also prevent water splashes (especially if the water line is near the upper limits of the tank) which will wet the rim, outside panels, stand, aquarium equipment and any nearby objects. Calcium may also begin to build up on the rim. Not to mention that your tank will lose more water than usual.

Last but not least, having an aquarium top will also help prevent your tank water from losing heat. This is especially true if the temperature outside of your tank is cooler than the one inside it. Having a cover will trap the heat in your aquarium and thus, keep your water running at a more constant temperature.

Glass vs. Polycarbonate Tops for Aquariums

The two main types of fish tank covers are glass and polycarbonate. Below, we will go through the pros and cons of each.

Should you buy a glass top over an polycarbonate top for your aquarium?

The more expensive option out of the two is glass. This type is great as it won’t bow or sag over time due to its thickness. It is also more easier to clean when compared to polycarbonate.

On the other hand, glass hoods are more prone to breaking, especially if you drop them onto a hard surface area. In our experience, our glass tops, while they are still functional, have chipped edges over the years due to some minor mishaps.

Glass Top Pros:

  • Won’t bow or sag over time
  • Easier to clean

Glass Top Cons:

  • More expensive on average
  • More prone to breaking if you aren’t careful

Should you purchase a polycarbonate cover over glass cover for your fish tank?

The major advantage polycarbonate tops has over glass tops is that the former is generally less expensive on average. It is also easier to cut (as you can use scissors) and drill if you want to customize the shape to fit your fish tank as well as any equipment cables going in and out. Last but not least, polycarbonate covers won’t break as easy when dropped.

As we already stated previously, one major flaw with polycarbonate hoods is that they can bow or sag over time. You can get around this by purchasing thicker covers (at least 1/4 inch, although closer to a half inch may be better). When compared to glass, polycarbonate is also a little harder to clean. Its surface is also more reflective and may cause a glare if you have your aquarium lights turn on.

Polycarbonate Cover Pros:

  • Less expensive on average
  • Easy to cut
  • Less prone to breaking

Polycarbonate Cover Cons:

  • Thinner polycarbonate and bow or sag over time
  • Harder to clean
  • More reflective than glass


We at Aquarium Blueprints highly recommend getting a cover for your fish tank as it has many benefits.

A top will prevent fish and other aquatic life from jumping/escaping as well as harmful bugs and/or chemicals from getting into your waters. It is also going to stop water from evaporating while providing insulation to keep your water temperature consistently warm at the same time.

While more expensive, we generally prefer glass tops as they don’t bow/sag, are easier to clean and don’t reflect light from your aquarium lights. You just have to make sure to be careful when removing the tops as they are more prone to breaking.

Polycarbonate is a good alternative, however, if you are looking for a more affordable option for a fish tank cover. You just have to make sure you are getting a sheet that is thick enough so that it won’t bow or sag over time.