The CaribSea Eco-Complete, otherwise known as CaribSea Eco-Planted, is one of the more popular substrates you can add to your fish tank.
So, is this product safe for Corydoras (aka the Cory Catfish)? You can find out in this article from Aquarium Blueprints.
Quick Summary
The sharp edges of the Eco-Complete and Eco-Planted are not ideal for the Corydoras as it may damage their barbels. Even if they managed to avoid injury, they are less likely to sift through this substrate, and completely dig their head in, when looking for food.
If you absolutely need to use Eco-Complete or Eco-Planted to grow life plants, then we recommend topping it with sand by at least one inch. With sand on top, the Cory Cat Fish should feel safer and will most likely interact with it more.
The structure of Eco-Complete and Eco-Planted
Eco-Complete and Eco-Planted are made of volcanic basalt rock. It is designed to absorb nutrients from the water column and then slowly release them. As a result, this is one of the better substrates for aquariums that have a lot of live plants.
These rocks feature sharp edges and really solid, however. It is also unlikely to break down in your tank.
About Corydoras
Corydoras, otherwise known as the Cory Catfish, are bottom-dwelling fish, which means that they like to hang out on the substrate. They enjoy sifting through and burrowing their hands at the bottom of the aquarium in order to look for food.
Is Eco-Complete or Eco-Planted safe for the Cory Cat Fish?
The sharp edges are not ideal for the Corydoras species. As we stated above, these fish like to sift around the substrate and bury their head in it.
By having Eco-Complete or Eco-Planted in your tank, you will risk damaging the barbels (aka the whiskers) of your pets. With that said, we kept Corydoras on sharp substrates before and they do just fine.
However, they are less likely to dig beneath the substrate. To eliminate the possibility of any potential injury, as well as see the most interesting behaviors of the Corydoras, we recommend using a fine sand substrate instead.
If you decide to go with sand, you can still use Eco-Complete or Eco-Planted as well. In order to do so, you need to place this substrate at the bottom and then top it off with sand by at least one inch.
By doing so, the top of the substrate should be sand only, giving your Cory Cat Fish a safe environment. Not to mention that you will still be able to grow live plants in the same tank as well.