Axolotl Tank Setup: Cold Water and No Gravel

Axolotl Tank Setup: Cold Water and No Gravel

Axolotl husbandry comes down to a short list of rules that matter a lot: keep the water cold, skip the gravel, and don't overthink the rest. Get those two things right and this is a genuinely manageable pet. This covers the setup itself, for the cost of building it, see our Axolotl cost guide, or the full Axolotl care guide for everything else.

Tank Size

A 20-gallon long tank is the minimum for one axolotl, with a 40-gallon breeder better if you're keeping two. Floor space matters more than height for this bottom-dwelling species. Use a secure lid, axolotls are capable of climbing out given the chance.

Water Temperature: The Defining Requirement

Keep the water between 60 and 68°F. Above 72°F starts to cause chronic stress, and it can become fatal in the mid-70s. Do not use a heater. Instead, plan for an aquarium chiller (or the JBJ Arctica Titanium if you want a quieter premium option) or, in cooler climates, fan-based cooling to keep temperatures in range, especially through warm months. A reliable thermometer makes it easy to catch drift before it becomes a problem, the health consequences of getting this wrong are covered in full in our Axolotl health issues guide.

Water Parameters

Ammonia and nitrite should both read 0, nitrate should stay low, ideally under 10 ppm, and pH should sit around 7.4 to 7.8. Check these with a water test kit. The tank needs to be fully cycled before an axolotl goes in, this isn't a species that tolerates an uncycled tank while it establishes itself.

Substrate: The Other Non-Negotiable Rule

Use fine sand with grains under 1mm, or skip substrate entirely and go bare-bottom. Never use gravel or small rocks. Axolotls are opportunistic eaters and will ingest loose substrate along with their food, and anything larger than fine sand carries a real impaction risk, one of the health issues covered in our Axolotl health issues guide. Keep juveniles under 5 inches on a bare-bottom tank until they're larger and less prone to accidental ingestion.

Filtration

Use low flow. Axolotls dislike current and can become stressed by filters designed for more active fish. A gentle sponge filter or a canister filter with the output diffused through a spray bar both work well.

Diet

Earthworms or nightcrawlers, cut into appropriate sizes for juveniles, are the nutritionally complete staple. Sinking pellets (salmon-based or invertebrate-formulated options) work as a supplement, and bloodworms make a good occasional treat. Adults eat every 2 to 3 days, juveniles daily.

A Few Other Details

Keep lighting dim, axolotls don't have eyelids and are sensitive to bright light. Provide hides for security. And keep the tank species-only, axolotls don't do well housed with fish, which can nip at their gills or outcompete them for food.

Once this setup is in place, day-to-day handling should stay minimal, see our Axolotl handling guide for when it's actually necessary, or browse the rest of our Amphibians care guide category and the Axolotl encyclopedia profile for more.

Sources & Further Reading