Question: Is Gravel Necessary?
Most people assume the gravel, or substrate, is only there to make their aquarium more attractive. If that is the case, is it a necessity or not?
Answer: Not an absolute requirement, but there are many reasons why it's recommended.
Biological Filtration
Perhaps the most important function that gravel serves is to provide a home for beneficial bacteria. Those bacterial colonies are necessary to eliminate waste produced by the fish, leftover food, and plant debris in the aquarium. If the bacteria don't have a comfy gravel bed to live in they will find other places, but may not grow in sufficient quantities to keep the aquarium safe for your fish.
If the tank is left with a bare bottom, it will be necessary to change the water more often in the aquarium to keep harmful wastes from building up. In the event the tank is heavily stocked, even frequent water changes may not be enough to keep ammonia and nitrites at bay.
Fish Habitat
Gravel of the appropriate type (i.e.: not too bold and glaring) can create a pleasant habitat for your fish. The more comfortable the habitat is for your fish, the less stressed and more healthy they will be. Stress is a major contributor to a compromised immune system in fish, leaving them more susceptible to diseases.
Substrates can provide a safe home for eggs laid by fish. Large-sized substrates allow the eggs to drop out of reach of hungry adult fish who wouldn't hesitate to eat their own offspring. Likewise, the infusoria that may be harbored in the gravel bed, is a good first food for fry.
In addition to reducing stress on the fish, substrates can also be used to improve the chemistry of the water. For instance, if your fish require hard water, coral gravel will increase water hardness.
Home For Live Plants
If you have live plants, substrate is critical, and second only to lighting in keeping your plants alive. The proper substrate in planted tanks can ensure your plants root well, have their nutritional needs met, and have a long and healthy life.
Aesthetic Appeal
Last but not least, substrates can provide aesthetic appeal for the owner and others who view the tank. Substrate hides the debris that inevitably is produced every day within the tank. Try having a bare bottomed tank for even a day, and you'll be amazed at how much 'junk' appears on the bottom.
In addition to hiding undesirable things, substrate shows off what you really want to see. A silver fish against bare glass doesn't stand out, but put a dark gravel on the bottom and suddenly the fish stand out.
Biological Filtration
Perhaps the most important function that gravel serves is to provide a home for beneficial bacteria. Those bacterial colonies are necessary to eliminate waste produced by the fish, leftover food, and plant debris in the aquarium. If the bacteria don't have a comfy gravel bed to live in they will find other places, but may not grow in sufficient quantities to keep the aquarium safe for your fish.
If the tank is left with a bare bottom, it will be necessary to change the water more often in the aquarium to keep harmful wastes from building up. In the event the tank is heavily stocked, even frequent water changes may not be enough to keep ammonia and nitrites at bay.
Fish Habitat
Gravel of the appropriate type (i.e.: not too bold and glaring) can create a pleasant habitat for your fish. The more comfortable the habitat is for your fish, the less stressed and more healthy they will be. Stress is a major contributor to a compromised immune system in fish, leaving them more susceptible to diseases.
Substrates can provide a safe home for eggs laid by fish. Large-sized substrates allow the eggs to drop out of reach of hungry adult fish who wouldn't hesitate to eat their own offspring. Likewise, the infusoria that may be harbored in the gravel bed, is a good first food for fry.
In addition to reducing stress on the fish, substrates can also be used to improve the chemistry of the water. For instance, if your fish require hard water, coral gravel will increase water hardness.
Home For Live Plants
If you have live plants, substrate is critical, and second only to lighting in keeping your plants alive. The proper substrate in planted tanks can ensure your plants root well, have their nutritional needs met, and have a long and healthy life.
Aesthetic Appeal
Last but not least, substrates can provide aesthetic appeal for the owner and others who view the tank. Substrate hides the debris that inevitably is produced every day within the tank. Try having a bare bottomed tank for even a day, and you'll be amazed at how much 'junk' appears on the bottom.
In addition to hiding undesirable things, substrate shows off what you really want to see. A silver fish against bare glass doesn't stand out, but put a dark gravel on the bottom and suddenly the fish stand out.
