Bare Bottom or Substrate? That is the Question!


Every saltwater aquarium is different and personal to the creator. As a result of this we have a vast range and styles of aquariums that all look unique. Some people go for a more natural appearance where as others aim for a simplistic look. What I am trying to say is there is no wrong way of setting up your tank. Its your choice! But how do you make this choice? Across the internet there is a vast amount of conflicting information surrounding every aspect of the marine aquarium. Here at Reef-fin we aim to simplify the information and break it down into manageable parts!


Which brings us to this post….



Within this post I am simply going to list the pro’s and con’s of going bare bottom or using substrate. I am not going to recommend any as I believe that is up to you. I will state which ones I use and why but overall its down to you, its your aquarium after all!


Silly Question – What does bare bottom and substrate mean?


Answer – Bare bottom simply means having no sand or gravel in your aquarium. Substrate is what you put on the base of your aquarium, such as sand or gravel. Easily answered right? see the importance of asking those silly questions? As I can’t see you nod or hear you say yes, I will just assume you did already.

Anyway…. bare bottom or substrate?







  • Gives the aquarium a clean look that many people find attractive in the modern home.
  • Easy to clean. Unlike sand or gravel no detritus can build up and cause your parameters to spike.
  • In time coraline algae will grow over the glass base giving a clean looking base to the aquarium. Others use coral to grow over the base of their aquarium.



  • Unnatural look to the aquarium that many dislike.
  • Many inverts, fish and marine critters like to live in the substrate, these animals are now off limits in your aquarium.
  • Substrate like crushed coral can buffer the PH and Hardness of the water keeping a constant and stable water chemistry.







  • Substrate gives the aquarium a natural look that many aim to have.
  • The use of sand, crushed coral or gravel is the home of many marine aquarium inhabitants that you can keep happy and healthy.
  • As stated above, the use of substrate and help bugger the PH and Hardness of your water chemistry, helping to maintain a stable environment.
  • Acts as a base support for the live rock to be mounted on. If your rock formation falls apart, the rock will land on the sand bed. With no sand bed the rock will land on the glass base of the aquarium with risk of chipping the glass.



  • Nitrate, Gases, Ammonia, Nitrite etc can often build up in a sand bed and once disturbed they can become toxic and spike parameters within your aquarium.
  • Cleaning can sometimes become hard work. Detritus can build up within a sand bed quickly and a structured cleaning schedule needs to be put in place.
  • Often looks messy and many critters and fish move the sand bed around on a regular basis, resulting in mounds of sand and rock formations been undermined.



Like I said it is totally up to you what you use within your aquarium. Often the type of aquarium you are wanting will directly affect your choice. I personally have a shallow sand bed that is around 1-2cm deep. It is enough for my critters to live in and keeps my goby happy. Cleaning is simple as the sand bed isn’t deep and most of my inverts turn over the sand bed on a regular basis. This is my personal choice. Aquariums with both bare-bottom and substrate can look amazing and house both fish and corals. Its up to you to weight up the pro’s and con’s of both and make your decision.


Things to think about;

  • What type of aquarium do you want to have?
  • What fish and corals do you want to keep?
  • Natural look or clean and modern?


Once you answer these questions you will have a rough idea of what you are heading towards. Put your answers against the pro’s and con’s of each to see what matches up the best. The best fit is what you should go for.


Good luck and keep reef-fin!