Why Do Cichlids Eat Sand and Gravel?

Cichlids are beautiful fish species and most people spend hours looking at them through their aquariums. If you have had a close-up look at your cichlids, you are probably wondering: “why do cichlids eat sand and gravel?”

Many cichlid species prefer gravel and sand substrate because it contains particles that aid in their digestion. You will notice that they forage through the substrate when scouring for their food. This usually happens when you use sand substrate since sand is packed with small particles that aid in their dietary.

It is also possible to find substrate in your cichlid’s mouth if they have been organizing the substrate to their liking. Usually, cichlids like Mbuna tend to move rocks and substrate with the aim of organizing it to their liking.

Hence, you can observe them eating the substrate and then spitting it out. This is a normal behavior for cichlids and should not be a call for concern. However, others like Malawi cichlids will eat the sand in search for organisms, rather than splitting it out.

Whatever the case, you should ensure that you furnish your cichlid with small-sized sand, especially if you notice this behavior. Unlike rocks or gravel, sand will help them continue being active without necessarily injuring their lips and gills.

Also, avoid large grained sand as they may limit the activity of small cichlids that want to dig. The size of the substrate is an important consideration when looking for the best sand and gravel for your cichlids.

Sand Vs Gravel: Which is the Best to Use?

Typically, sand and gravel are the most common types of substrate that is found in the bottom of the aquarium. Most cichlid owners find these two substrates quite similar and most would like to know which is better.

Sand and gravel are quite different and each has its own pros and cons when it comes to using in your cichlid’s tank.

One of the advantages of gravel substrate is its capability to allow water to flow through it. This means that substrate filters itself, and this prevents buildup of bacteria and amoeba in the long run.

Another reason why fish owners may opt for gravel substrate is because of its weight. Unlike sand, gravel is heavy and this prevents it from getting dragged into the tank filters. Hence, gravel is unlikely to clog the filters. Plus, they come in a plethora of colors to choose from.

In the case of sand substrate, most aquarium owners believe that it is the most suitable choice for their cichlids. Naturally, the habitat of cichlids is sandy lakes and putting sand in their aquarium will make them more comfortable.

The other advantage of sand substrate is that it contains small grains that act as dietary aid for the cichlids. For some, a sand bed creates a good environment to build their nest. Plus, the food and plant matter is more likely to float on sand where fish can easy access it.

However, unlike gravel, sand substrate lacks the ability of letting water flow through it. Therefore, this can encourage buildup of bacteria and amoeba.

Ultimately, both sand and gravel will do well for your cichlids. However, you may want to use sand for smaller cichlid species and gravel for larger cichlid species like Oscars.

How Do I Choose the Best Cichlid Substrate?

Choosing the right substrate for your cichlids is crucial to ensure their overall wellbeing. The best substrate will help maintain proper PH to ensure prolonged health of your cichlids. This is especially important when keeping African cichlids since the water their original habitat in Central Africa has high PH and hardness.

Therefore, you need to choose your substrate depending on where your species hails from. Furthermore, you will need to add cichlid salt or buffer in order to maintain the proper alkaline PH and GH levels.

Since this can be costly, especially for beginners, it is recommendable to use gravel like crushed coral, coral sand, crushed oyster shell, aragonite or dolomite. By using these substrates, you won’t need to add any buffers to keep the water conditions favorable for your cichlids.

Something else to keep in mind when making your selection is the substrate size and texture. It is recommendable to opt for small or medium-grained sand or gravel to allow your cichlid to dig into the aquarium floor with ease. Also, finer gravel or sand can be challenging to keep clean and dead spots can sit at the bottom of the tank.

When it comes to the texture, smooth substrate is a good choice. Since your cichlid loves to dig, smooth substrate will enable them to keep active without injuring themselves.

Why Do Cichlid Dig Holes in the Substrate?

Typically, cichlids will dig holes in the substrate when they are digging for food, breeding, sleeping or digging a den.

  • Digging for Food

If you catch your cichlid foraging through the substrate, they are probably looking for their food. They will do this especially in sand substrate since it contains small grains that help with their digestion.

  • Fleeing

Other times, cichlids will more around rocks or gravel when they are fleeing from bigger fish. This helps them to get out of the meaner fish’s sight and hide in a safer place.

  • Breeding

If your cichlid wants to lay eggs, they will most probably move around rocks or gravel to create spawning pits. This behavior is common in different cichlid species like the African cichlids, small ram cichlid and larger earth-eater cichlid. This is more of a defense strategy as they are looking for a safer place to keep their babies from other fish.

  • Courtship

Some cichlids will dig into rocks when they are in the courtship period. They may do this behavior if they are fighting over courtship partners or if the other partner is not cooperating in the process.

  • Territoriality

Oftentimes, cichlids, just like other fish, may move the rock and gravel in the aquarium for purposes of creating their territory. This is not surprising since cichlids are naturally aggressive and territorial.

Why Do Cichlids Rub Themselves Against Rock or Substrates?

Cichlids that are stressed or uncomfortable are likely to brush against objects in the aquarium, something that is called flashing. Usually, this occurs when the water in the aquarium is in a sorry state or due to an illness.

One of the illnesses that are likely to cause cichlids to run themselves is Ich. This is a common protozoan parasite that causes cyst, similar to grains of salt, on the fish. Therefore, the cichlid may try to rub against a rock in an attempt to remove the parasite.

The other fish disease is Velvet. This parasite is similar to Ich only that it causes much smaller cysts that look like sugar. Similarly, cichlids with this parasite will rub against a rock to try and remove the parasite.

Nonetheless, it is important to note that cichlids like the African cichlids rub themselves on the rock for breeding purposes. Although some cichlids create spawning pits, other may just breed o the rocks. Hence, the act of rubbing on the rock or gravel is basically to clean it before they lay their eggs.

If this is the case, the cichlid will rub its lips or face on the rock rather than its body. Therefore, there is no call for concern as this is just a natural behavior.

Author Profile

Adam Edwards
Hi, my name is Adam and I'm an aquarium enthusiast! I didn't discover the joys of being an 'aquarium fanatic' (as some of my friends call me!) until I was in my 20's. When I first started out I found it difficult to find all the information I needed so I started this website to compile all the useful information I can think of. Enjoy!