Crushed Coral vs live sand

Crushed Coral vs Live Sand

Home aquarium keepers often face a dilemma when trying to decide which substrate to use in their tank. Depending on what kind of life you are keeping in your saltwater aquarium, you will require different materials. 

With new live sand substrates on the market today, many aquarium keepers prefer live sand to crushed coral. Live sand mixtures allow you to customize the granule size, balance the tank’s pH level better, and reduce debris. Conversely, crushed coral works well in high-flow saltwater tanks as it has larger pieces of limestone, shell, and other materials. 

To learn more about the differences between these two kinds of substrates, keep reading. We’ll unpack the instances in which crushed coral and live sand work best, whether or not you can mix the substrates, and more. 

Is Crushed Coral Better Than Sand?

There is some debate regarding whether crushed coral or sand should be used in saltwater tanks. In recent years, though, many aquarium keepers have turned to sand mixtures because they offer more potential benefits. 

Variety of Grains

One of the key advantages of using sand is that you can get this substrate in a variety of grain sizes. The size of the grains will affect the filtration of the water in a saltwater tank, so the higher the water flow is, the larger the granule size you want. 

This way you can avoid lots of matter getting stirred up all the time. Sand allows you to pick the grain size, whereas there are fewer size options for crushed coral. 

Benefits to Ecosystem

Live sand can also help with different organisms and microorganisms in your tank, especially if you keep a reef tank. The sand that sits at the bottom of the tank becomes a home for creatures like plankton, crustaceans, fish, and more. 

Specifically, the bacteria and other microorganisms that live in the sand are important to feed on nitrite and ammonia so that they don’t have a toxic effect on the ecosystem. 

Furthermore, live sand in tanks is beneficial because it helps you to better manage the pH level of the water, which is crucial to maintain. In particular, aragonite sand works really well in saltwater tanks, as it dissolves slowly at a slightly basic pH level. 

Fewer Detritus

Did you know that using live sand could actually provide essential food and nutrients to some of the creatures in your aquarium? 

There are creatures that eat the detritus, so it doesn’t build up in the substrate. These creatures in turn get eaten by the corals in a reef tank. So, the live sand actually contributes to an all-around better functioning tank. 

Can You Mix Live Sand And Crushed Coral?

Although there are specific benefits to using live sand, there are still instances where you might want to use crushed coral. Crushed coral has the benefit of quickly raising the pH level of your tank if it has gotten too acidic. It also has a larger grain size, which is good in tanks where the water flow is higher. 

But you might want to mix live sand and crushed coral together to get the best of both worlds. In reality, you can mix these two substances in your tank, but you do run some risks in doing so. 

If you’re going to mix the two, you ideally need to clean the crushed coral before you add sand to it. Otherwise, you’ll essentially trap in any current detritus that have built up, and you’ll struggle to get rid of it. You also run the risk of making your substrate too thick and coarse, which makes it hard to sift and clean going forward. 

But, if you do it right, you could mix the two and effectively prevent new detritus from getting trapped in the substrate. 

Can I Use Crushed Coral As Substrate?

Yes, crushed coral is an effective tank substrate choice when it comes to freshwater tanks. But when it comes to saltwater tanks, you’re likely going to have more success with a sandy substrate. 

In freshwater tanks, crushed coral affects the pH level, which helps to maintain the acidity of the water long-term. But in a delicate reef tank, for example, the limestone in the crushed coral could affect the pH level too much or too fast, resulting in consequences. 

Crushed coral also makes an aesthetically pleasing substrate for those who care more about that factor, but keep in mind that you want to keep the health of the organisms at the forefront. 

And again, detritus is much more likely to get trapped in the substrate if you use crushed coral, requiring more maintenance overall. 

Is Crushed Coral Good For Reef Tank?

The benefits of live sand in reef tanks pretty much outweigh the benefits of using crushed coral in these tanks. The many microorganisms and saltwater creatures that coexist with coral need the detritus and other matter in live sand to sustain themselves. 

In turn, this keeps the tank clean and maintained, and properly functioning as an overall ecosystem. 

Furthermore, reef tanks typically need a well-balanced water flow (not too high), so the large pieces of crushed coral aren’t really necessary in a moderate flow reef tank. Crushed coral also has a significant effect in terms of raising pH, GH, and KH levels in tanks. Therefore, to strike a delicate water balance in a reef tank, crushed coral might be too intense. 

Final Thoughts

When you’re keeping a home aquarium, you need to find the ideal type of substrate to sustain the organisms you care for. In a saltwater tank, it’s usually best to use live sand for its various benefits, including improved pH maintenance, a variety of grain sizes, and reduction of detritus.

Crushed coral has its benefits in freshwater tanks and tanks that have a high flow, but most of the time, crushed coral’s disadvantages outweigh its benefits. Namely, crushed coral needs more maintenance, can change the pH too quickly, and becomes a pesky environment for detritus that needs to be cleaned.