Aquarium Substrtates. How to choose aquarium substrates.

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Aquarium Substrates Tropical

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This information sheet has been designed to help you make an informed choice.

How To Choose Aquarium Substrates.
An aquarium substrate is the material chosen to cover the bottom of the aquarium. It can, depending on the system type, be for purely decorative adornment, it can be an essential additive needed to maintain the water chemistry or it can be a major component of the aquarium filtration system. Choice of substrate can also be important if trying to duplicate a natural eco-system such as the sandy bottom of the Amazon or the pebbly bottom of a fast flowing African stream.

Types Of Substrate.

Aquarium Pea Gravel. Aquarium Pea Gravel is the most commonly used substrate material. It is available in a number of different grain sizes with the most popular being 1/8th (3mm) and 1/4qtr (6mm). Avoid using larger sizes (Unless a necessary part of an eco-system aquascape as above) as the voids in-between each gravel grain trap waste that will pollute the aquarium water as it decays. The smaller of the two grain sizes is best used in planted systems and the larger in aquariums fitted with under-gravel filters. (Mathematically a finer substrate is a more efficient biological filter medium as it has a larger surface area providing a greater area for colonizing by aerobic nitrifying bacteria. In practice, however, small pea gravel will tend to work its way through the filter base and clog the void underneath so reducing the filters efficiency). A good quality Pea gravel will be relatively inert and will not, therefore influence the water quality, primarily the Ph (Acidity or Alkalinity) and Kh (Temporary hardness). Choose a Lime free gravel so that water chemistry is not affected and check for the presence of small pieces of sea shell which, whilst not a problem if used in coldwater systems may produce un-desirable results in a Tropical system. Pea gravel is probably the cheapest substrate material available. Use between 10lb (4.5kg) to 15lb (6.8kg) per square foot (30 square cm) for best effect.

Nutrient Substrates. Nutrient substrates are clay based gravels enriched with trace elements essential for successful plant growth and are highly recommended for aquariums where lush planting is desirable. The trace elements are released from the gravel over a long period so ensuring continued success. Using nutrient gravel such as Aquagrit, is an easy way to achieve good results with plants.

Aquarium Sands. Aquarium sands are usually used in Tropical Aquarium Systems where a soft substrate is required. This may be to re-create a particular habitat or to provide perfect conditions for Catfish with barbells that may be in danger of damaging themselves whilst rooting through a rougher edged substrate material. Mormyrids (Elephant Nose Fish) are another species that will benefit from a sandy substrate, as will many Eels and Eel like fish. Aquarium sands are usually inert (Except for Coral Sand) so will not affect water chemistry. Most Commonly used in a natural beige colour there are, however, artificially coloured versions available but these can be quite expensive if used in any quantity. It is because of this that coloured sands are usually used in Bowls and small aquaria. Use between 11lb (5kg) to 16lb (7.25kg) per square foot (30 square cm) for best effect. Avoid creating too deep a sand layer, as there is a possibility of compaction occurring. This may produce anaerobic “Dead Spots”, which could result in deteriorating water conditions and stock loss.

Coral Gravels. Coral Gravels are a porous, natural material created by the action of wave and weather on the dead coral skeletons shed by a reef as part of its natural cycle of birth, death and re-generation. Average grain size is about 5mm and for coverage allow between 9lb (4kg) to 13lb(6kg) per square foot (30 square cm). Coral gravels can be used in Coldwater, Brackish, Marine and Rift Valley Cichlid aquarium systems. It can also be used in a Livebearer community aquarium but not in any aquarium containing fish intolerant of the harder water, more alkaline conditions that this gravel will tend to create. Because of the porous nature of the material it also performs well as a biological filter media over an under gravel filter.

Coral Sands. Coral sands are produced very like coral gravels above but have been ground down by the elements to a much finer grain size. They can be used in the same aquarium systems as Coral Gravel but are only used with under-gravel filters if the filter plate is first covered with a “Gravel Tidy”. This is a fine mesh like sheet, which allows the passage of water but holds back the sand. The porosity and fine grain size of Coral Sands provides a massive surface area for bacterial colonization and it is because of this that it is used in other types of filtration systems, from sand pressure filters to commercial tower systems. For Aquarium use allow around 9lb (4kg) to 13lb (6kg) per square foot (30 square cm). See also the note on “Compaction” in “Aquarium sands” above.

Quartz Gravel. Quartz Gravel is often available in a jet-black colour and is used to create a very different and dramatic aquarium base medium, which acts as a complimentary canvas to other decoration and plants placed upon it. It is chosen also as a substrates for very modern style aquariums that bear little relationship to the natural environment but make bold design statements that in the right setting can look amazing.

Coloured Gravels. Coloured Gravels are available in a large variety of hues and shades and are a great way of bringing a small aquarium or bowl to life. Take care to avoid cheaper varieties that can leach colour into the aquarium. The best coloured gravels are those that are epoxy coated as these are inert and colour fast. Estes are a company that produces over 50 coloured gravels and pebbles that are vibrant and safe.