One of the most common arguments against bare bottom tanks is that axolotls “slip” on the glass, making them uncomfortable or stressed. In reality, slipping usually indicates that the water flow is too strong for the axolotl, not that the tank bottom is unsuitable. Axolotls should be able to walk calmly along the glass without sliding, provided filtration and flow are properly adjusted.
Stress Comes From Other Factors
The assumption that axolotls become stressed without substrate is largely a myth. What truly affects the well-being of an axolotl are environmental conditions such as bright lighting, high temperatures, poor water quality, or lack of hiding places. Many axolotl owners, including experienced breeders, have raised axolotls in bare bottom tanks for years without any signs of stress.
Advantages of Bare Bottom Tanks
Bare bottom setups offer several practical benefits:
- They eliminate the risk of impaction, which can occur if axolotls accidentally swallow gravel or coarse substrate.
- Cleaning bare bottom tank is also much simpler, as waste and uneaten food are easy to spot and remove. This contributes to more stable water chemistry, which is essential for axolotl health.
- Bare bottoms also make it easier to collect eggs after spawning. For juvenile axolotls in particular, this is often the safest and most recommended option.
The Aesthetic and Biological Trade-Offs
Despite their benefits, bare bottom tanks are not without drawbacks. Some people feel that axolotls gain better traction on sand or tile surfaces, making movement appear more natural.
Substrates like sand also provide additional surface area for beneficial bacteria, helping support the nitrogen cycle, and allow anchoring of live plants, which improve water quality. A bare bottom, by contrast, leaves the filter to carry most of the biological load.
Additionally, some aquarists prefer the more natural look that sand or fine substrates bring to the aquarium.
Verdict
A bare bottom tank does not inherently stress axolotls. When maintained correctly—with gentle water flow, proper hides, and dim lighting—it can be one of the safest and easiest setups, particularly for young axolotls.
Ultimately, whether to keep a bare bottom or introduce a safe substrate comes down to personal preference and how much maintenance you are willing to commit to.
Both approaches can work well, as long as the axolotl’s core needs for clean water, cool temperatures, and low stress are consistently met.