all about aquarium gravel

Gravel is one of the first purchases that many aquarists will make whether they have a freshwater, saltwater, reef, goldfish, cichlid or any other type of set-up. But what are the benefits of aquarium gravel and is it a necessary inclusion?Substrate has been an important aspect of aquaculture for many years. But filtration technology has improved dramatically in recent times as has our understanding of water chemistry. Undergravel filters were once thought to be essential, making the inclusion of gravel equally essential. But this type of system is now largely obsolete and gravel has become an option rather than a requirement. Some enthusiasts now advocate bare-bottom tanks. Others swear by substrate.


An aquarium which is easy to clean obviously has its advantages. Here, a bare-bottomed tank will make life easier as you won't need a gravel vacuum. It is easier to scrub any algae off of glass and if you have a reef aquarium, rocks and debris are less likely to end up in places you cannot reach.


Here aquarium gravel is a major boon. Natural environments do not feature glass bottoms! The inclusion of substrate creates a more natural look and coloured gravel can be used to produce striking visuals. In addition, most live aquarium plants will struggle to survive without substrate to root into. In the wild, substrate is crucial to many creatures as it provides somewhere for them to bury themselves or vital camouflage from predators.

Water Chemistry

Both substrate and bare-bottomed tanks can improve or detract from water quality. Some substrates, including crushed coral, will enhance hardness and boost the PH level of the water which is beneficial for a saltwater tank. A tropical tank will not fare so well. A fluorite substrate can be helpful to freshwater tanks and provide minerals for plants. On the other hand, substrate can trap waste and when it decomposes, nitrate, phosphates and ammonia in the water will increase leading to unhealthy fish and algae blooms. Waste is much easier to extract from a glass bottom.

Visitors to Your Tank

You may find that you receive unexpected visitors to your saltwater tank including snails and flatworms. Here a bare bottom will help you to get rid of them and most of these unwelcome critters live or reproduce in substrate. Unfortunately, a bare bottom will also keep away beneficial copepods and amphipods which provide a natural food source for some of the pickiest fish. You need to be sure that you can do without the good visitors before you rid yourself of the baddies. Choosing whether or not to add substrate to your aquarium will depend on which type of tank you have and the nature of your fish stocks. Generally, coral-only reef tanks can go bare, planted freshwater tanks cannot. Freshwater fish-only tanks might not require gravel but saltwater fish-only tanks will do better with it. You may have to experiment in order to achieve the perfect balance. Seek expert advice if you are unsure which way to go. At Krafty Koi we stock a wide range of to suit all kinds of set-up.

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