change in the pH and hardness of aquarium water.
Also, some fish like to sift the substrate and sand can be an irritant due to its small particle size. The recommended level of gravel for tanks up to 55 gallons is a two-inch layer. For tanks larger than 55 gallons, two to three inches should be sufficient. Another more common reason, is that some rocks or gravel are composed of materials that can cause a change in the pH and hardness of your aquarium water, which in turn can be harmful to your fish. Sand. After gravel, sand is the next most commonly used substrate for freshwater aquariums. Some species of fish enjoy burrowing in small substrates, making sand a good choice for those fish. One advantage of sand is the fact that most debris does not penetrate below the surface. Also commonly referred to as substrate, the kind of gravel you choose can have a substantial impact not only on the visual appeal of your tank but also the well-being of your freshwater fish and any live plants you place in the habitat. Contents. Gravel is the most frequently used aquarium substrate, and with good reason. It comes in a variety of sizes, shapes and colors, and is a good all-purpose substrate. As with any substrate, it is important to know the impact that the chosen gravel can have on the water chemistry. For freshwater aquaria, gravel is the most common substrate. To prevent damage to fish, gravel should not be sharp. Aquarium gravel can be as coarse as pea-sized or as fine as 1–2 mm. Gravel in a freshwater aquarium. The substrate of an aquarium refers to the material used on the tank bottom. It can affect water chemistry, filtration, and the well-being of the aquarium's inhabitants, and is also an important part of the aquarium's aesthetic appeal. The accumulation of waste detracts from the visual look of your aquarium. The waste produces cloudy water, and this is the main reason why pea gravel is the best gravel for goldfish tanks. There are various types of gravels that can give your aquarium a particular theme.
http://homeaquaria.com/freshwater-aquarium-gravel/ http://freshaquarium.about.com/od/termsandtables/f/outdoorrock.htm http://freshaquarium.about.com/od/aquascaping/tp/Types-Of-Substrate.htm http://homeaquaria.com/freshwater-aquarium-gravel/ http://freshaquarium.about.com/od/aquascaping/tp/Types-Of-Substrate.htm https://en.wikipedia.org/wiki/Substrate_%28aquarium%29 https://en.wikipedia.org/wiki/Substrate_%28aquarium%29 http://howtotakecareofgoldfish.com/why-is-pea-gravel-the-best-gravel-for-your-goldfish-tanks/
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