So you have your first aquarium, second aquarium etc. one of the most exciting aspects is decoration and yes substrate comes into that but there are other important aspects to consider.

Hardscape literally refers to the solid abiotic (non-living) things within the aquarium the rocks, the wood, the general décor. It’s the most creative aspect of an aquarium.

While you might see many aquariums without hardscape of any kind and even without plants, the presence of these items offers so much vital enrichment for fishes. I should write an article on the science behind it as there has been research into creating enrichment for fishes.

This hardscape is really how we can meet a lot more of the fishes behavioural environments but some physiological requirements: many fish like to dig (covered in substrates); others like crevices and caves and; at the end of the day it changes the landscape a bit for the fishes. In some way and for many fishes it really doesn’t matter what you add as long as it’s safe.

How can you be sure it’s safe for fishes though?

The easiest way is buying any hardscape from an aquarium store. Ideally for rocks ensuring it’s not something that would make the water harder, staff in stores are more then happy to help out there. Some rocks might need quite a bit of rinsing and maybe cleaning with a toothbrush under the tap like dragon rock. For any hardscape the aquarium store is a good option.

Collecting your own I will cover but not in this aspect of the website, it’s more risky and requires research or consideration.

So lets deep dive down the two major options:

Wood

A big disclaimer, as a scientist specialising in Loricariids I will state wood is not needed for food or digestion by plecos, this article says why, it can be great for behavioural enrichment though in some genera also explained there. Your options between the two is rather personal but depends on how much you want to replicate a fishes environment.

I use a lot of wood, it tends to be less heavy then rocks and rocks smashing against the glass is always a worry of mine. The unusual shapes allow for me to pile it up and over pleco caves to create many crevices and hiding places.

Wood tends to grow a few more films and algaes which I personally prefer.

A big issue with wood for many is it can leach compounds known as tannins and while they can benefit some fishes they are not sightly to many aquarists. For discus owners tannins are certainly not wanted as can make a fish much darker, sometimes difficult to repair. The great thing is that chemical filtration such as activated carbon, polyfilter or purigen can remove these, replace every 4-6 weeks. Over time wood can stop leaching these compounds.

Rocks

Equally as great, soo many different colours and shapes. They are heavier but such a wider variety of options, they still can grow things on their surfaces. I feel rocks aesthetically has a lot more choices but it can be sharper.

Rocks definitely have to be underrated, these are found in so many freshwater ecosystems and really need more credit!

I hear botanicals mentioned, should I add them?

So these are largely to replicate the natural environment of certain fishes, not all fishes and there is some debate into aspects of their use. As they can and do alter the water chemistry I will discuss them later on in the Furthering Freshwater Fishkeeping aspect of the website; alternatively now CE Fish Essentials and Tannin Aquatics discuss the topic. It is aimed at black water fishes and an important reminder is not all of South America or South East Asia is black water, large areas are not.