Substrate in a Seahorse Aquarium-Bare Bottom vs Sand

Substrate-Sand vs Bare-bottom

Choosing whether to setup your aquarium bare-bottom (no sand) or with sand is a personal preference. There are benefits to both options. Aquascaping with liverock is also important. Creating an open rock structure will allow for better water flow and help prevent detritus build up. We will be discussing pros and cons to having sand or going bare-bottom with your seahorse aquarium. 

Photo credit Savannah D. 


Having sand in the aquarium is more aesthetically pleasing to most keepers. A sand-bed in the aquarium creates a more natural look. You can also have a variety of sand dwelling clean up crew inverts including Nassarius snails, Cerith snails and sea cucumbers which really need a sandbed to thrive. Nassarius snails are especially good clean up crew with seahorses as they help eat leftover meaty foods. You will also have a lot more beneficial micro-fauna with a sand-bed.

If you are interested in keeping other tank-mates with your seahorses this may also play into your decision on whether to go bare bottom or with sand. Some species of gobies are substrate dwelling and really do best with a sand-bed. In addition, there are a variety of beautiful rooted macro-algaes that can be kept with seahorses too. It is important to really research and understand the needs of the animals you wish to keep.

If you decide to go with sand in your seahorse aquarium we recommend using an aragonite substrate in the ~0.5-1.5 mm range. CaribSea Fiji Pink aragonite is our favorite. Avoid larger substrate such as crushed coral. Over time larger substrate will allow for a build up of detritus and waste. We have seen a lot of hobbyist have issues keeping their seahorses in an aquarium with coarse crushed coral substrate.

Having sufficient water flow near your sand-bed will also help prevent build up of waste and keep the aquarium healthier.

Photo credit Savannah D.

Bare Bottom (no Sand)

Having a bare bottom aquarium (no sand) can make keeping your aquarium cleaner much easier. With no substrate on the bottom it is easy to make sure waste isn't building up in the aquarium. Build up of detritus (waste) in the aquarium creates instability and can promote nasty bacterial growth that can make your seahorses more susceptible to problems. Keeping build up of waste out of the aquarium is one of the keys to long term success with seahorse keeping. If your aquarium is bare-bottom and you are getting a build up of food or waste on the bottom you need to add more water flow or tweak the water flow at the bottom of the aquarium.

From our experience, we find it much easier to keep the aquarium clean and water quality up with having no sand in a seahorse aquarium.

Photo credit Savannah D. 

We hope you find this article helpful. If you have any questions please reach out. We are happy to help and look forward to hearing from you. Special thank you to Savannah Duda for supplying many of the photos in this article her personal seahorses acquired from our farm.