Use of Bottled Water for Amphibians
By Jennifer Macke
In most cases, amphibians can live perfectly well in dechlorinated tap water. However, there are several situations in which you may want to use bottled spring water instead:
- You have a reason to think that your tap water is not suitable. For example, if you have well water and you know that the water is high in metals. Or if the pH of your tap water is above 7.8 or below 6.4. Or if your tap water has extreme mineral hardness.
- You have problems with cloudy water in a newly set-up tank. This cloudiness is caused by a sudden growth of bacteria feeding on the nutrients present in some tap water. Starting a new tank with spring water will eliminate this problem.
- Your tank is testing positive for ammonia or nitrite, and partial water changes with dechlorinated tap water fail to bring the level down. Consider overcrowding and overfeeding as likely causes.
- Your amphibian is sick and you want to treat it in as clean an environment as possible. Spring water usually carries fewer nutrients that could nourish bacteria or fungi.
I recommend Deer Park and Poland Springs spring water, based on my own tests and on the recommendation of the book Newts and Salamanders, referenced below. I have tried several brands of spring water that had unacceptable pHs. When you buy the first jug of spring water, test the pH. It should be between 6.4 and 7.8. If not, try a different brand until you find one with a pH in this range. Here are the pHs of several spring waters that I tested. (Note that these tests were done in 2001, and products may have changed. These results are shown as an example, not as a recommendation for any particular brands.)
Spring water brand | Approximate pH |
Deer Park | 6.8 |
Poland Springs | 6.8 |
Arrowhead | 7.0 |
Dannon | 8.4 (too basic) |
Sams Choice (Walmart) | <6 (too acidic) |
Kroger Brand | <6 (too acidic) |
Other kinds of bottled water
Do NOT use water that is labeled as "distilled" or "drinking water". Distilled water (or Reverse Osmosis water) has virtually no ions in it, so it causes more work for the amphibian's kidneys. It may be used to replace water lost to evaporation, but an animal should not be kept in pure distilled or RO water. Bottled "drinking water" is usually just filtered tap water and probably no better than your own tap water.
The Wright & Whitaker Amphibian Medicine and Captive Husbandry book says:
"Amphibians rely upon the water in which they live to provide them with many of the constituents needed to carry out metabolic processes... Distilled and reverse osmosis water contain none of the elements required by amphibians and should not be used without modification."
Furthermore, there are many scientific studies showing that amphibians kept in distilled water undergo specific physiological changes. These changes could be interpreted as stressful. Thus, I believe it is best to avoid distilled water (despite the continued recommendations of some authorities).
One issue to consider is what kind of water does this animal inhabit in the wild? Some water sources, such as rain water, are not very different from distilled. For animals adapted to this, distilled water may be an acceptable choice. Also, animals accustomed to soft water might be stressed going into hard water. These factors should be considered if bottled water is used.
Filtered water
Tap water filtered through a drinking water filter, such as a Brita or Pur filter, should theoretically be good for amphibians. These filters should remove all chlorine, chloramine, chlorine by-products, metals, and other contaminants, while leaving beneficial minerals, such as sodium, calcium, and magnesium. However, there have been specific reports of amphibian problems and disasters resulting from using charcoal-filtered water. Carbon-filtered was found to be linked to the development of spindly leg syndrome in multiple species of frogs (Kowalski 2007). Therefore, using carbon-filtered water is not recommended.
References:
Indiviglio, Frank. Newts and Salamanders. Barrons: 1997.
Kowalski, Edward. "Spindly Leg Syndrome, a Review". In Leaf Litter Volume 2, Winter 2007.
Parrish, Michael. Distilled Water for Amphibians. (Web article no longer available).
Wright & Whitaker. Amphibian Medicine and Captive Husbandry. Kreiger: 2001.
© Jennifer Macke 2001. Revised January 7, 2004. Revised November 2007. Revised April 2008.