Axolotl Tank Cleaning and Water Chemistry

Once you have your nitrogen cycle up and running, you’ll just need to do some regular maintenance to make sure that your water chemistry stays stable and your axolotls stay happy and healthy. For this, you’ll need to keep using your water testing kit (remember, chemical liquid test not paper strips, strips are prone to inaccuracy!).

Safe Parameters for Water Chemistry

Ammonia: 0ppm

Nitrites: 0ppm

Nitrates: 20-40ppm

pH: 6.5-7.8



Ammonia: The natural byproduct of the decomposition of waste and leftover food. Remember that axolotls have thin skin and are especially susceptible to absorbing harmful chemicals from the water.Concentrations of 1ppm or higher will kill your axolotl after just a few days. Even at lower concentrations, over time ammonia will weaken your axolotls immune system and make it susceptible to disease or infection. In a properly cycled aquarium ammonia will be broken down by bacteria into nitrite very quickly.

Nitrite: Nitrite are created by the breakdown of ammonia by bacteria in your tank. If your tank is properly cycled you will not have any reading of nitrites, as just like the ammonia->nitrite conversion the nitrite->nitrate conversion is performed by bacteria almost instantaneously. Like ammonia, a concentration of 1ppm or more will quickly kill your axolotl as nitrites have a suffocating effect.

Nitrate: Nitrate is the final product of the Nitrogen Cycle in your aquarium. Its presence indicates that the beneficial bacteria are doing their job of breaking waste down into this significantly less toxic byproduct. A tolerable range for nitrate levels is 20-40ppm, but in higher concentrations can be toxic. Nitrate levels can be managed with water changes, we go into the details of changes and cleaning below.

pH: pH is a measurement of the acidity of your water. The pH scale runs from 0-14, with 0-6.9 being acidic, 7 neutral, and 7.1-14 being alkaline. The safe range for axolotls is about 6.5-7.8. pH levels higher than this should be avoided as a high pH has the effect of multiplying the toxicity of any ammonia present in the water.


Tank Cleaning

A safe guideline for tank cleaning is to (in conjunction with water testing) do a water change of about 20-25% per week. Remember to treat the water with a water conditioner beforehand to remove chlorine/chlorinates. They can destroy your nitrogen cycle. The water change should help to keep you keep your nitrate level in check, and keep your axolotls happy and healthy.

Never completely empty out your tank and scrub it down, this will cause the tank to lost its cycle and you will be starting from square one. First off, to remove waste effectively you’re going to want to invest in a good gravel vacuum. This will save you a lot of time and effort in removing waste and leftover food buildup.

Here’s a helpful video on how they work and how to use one:




Another good tool to have is a turkey baster, since these are optimal for spot cleaning. They let you suck up isolated pieces of food or waste you may spy on the tank floor without having to pull out your heavy duty cleaners. Turkey basters can also be useful in feeding your axolotl.

Next, keep in mind that when you rinse the filter to clean it or clean off any of the tank ornaments, this should be done using tank water. At risk of sounding like a broken record, tap water will disrupt or destroy your cycle. You want to avoid introducing chlorine or chlorinates to your tank as all costs, and you need to be especially careful with your filter, which is where your beneficial bacteria build up.

Keep to these steps and monitor your water chemistry with weekly tests, and you should stay problem free!


Keep Reading: Axolotl Care Sheet

  1. Tank Size and Requirements
  2. Filter and Water Temperature Requirements
  3. Starting a Nitrogen Cycle
  4. Substrate Requirements
  5. Hides, Plants, and Decor
  6. Tank Cleaning and Water Chemistry – Current Page
  7. Diet and Nutrition
  8. Illness, Injury, and Treatment
    1. Fridging Guide
    2. Salt Bath Guide
  9. Additional Reading and Resources