Choosing an Aquatic Caecilian
The aquatic caecilian is an undemanding creature that is often mistakenly called an eel. It breathes air, and periodically rises to the water surface to gulp in a fresh breath. The caecilians are tropical amphibians, distinct from frogs and the salamanders. The caecilians belongs to the family Gymnophiona and there are several species.
Only one or possibly two fully aquatic neotropical forms enter the pet trade. This species, Typhlonectes natans, is often referred to by persons who have heard the name pronounced but not seen it written, as the Sicilian eel.
Origin and Life Span
In the wild, the aquatic caecilian dwells in mud-bottomed areas of quiet waters – in oxbows and other such habitats – that may occasionally dry seasonally. Should this happen, the caecilian burrows down into the moisture-holding mud to await the replenishment of the surface water during the next rainy season.
To date, the reported longevity for a captive aquatic caecilian has been just over 4 years. It is probable that at least twice that time span is attainable.
Appearance
A second vernacular name rather aptly describes the appearance of aquatic caecilians. They are often referred to as "rubber eels," and that is pretty much what they look like. Aquatic caecilians are more easily identified by what they lack, than by what they have. These are mud-colored, cylindrical amphibians, without appendages, and with the eyes covered by translucent skin.
The legless aquatic caecilian is clad in mud-gray on top and is a little lighter below. In addition, the aquatic caecilian is finless, tailless, and lacks functional external eyes. The eyes are reduced to light-sensitive "dots" on each side of the head. Vertical (costal) grooves are very evident for the length of the caecilian's body, especially on the inner side of a body curve.
Housing
Although neither brightly colored nor outgoing, caecilians are interesting creatures. A tank containing four or five specimens may look empty by day, but fairly seethe with activity at night. One to four or five caecilians can be kept in a 10-gallon tank.
Caecilians can be kept either in a planted or a non-planted aquarium. For a planted aquarium, you will need to provide suitable lighting to stimulate plant survival and growth. Rooted plants are often uprooted by the burrowing activities of the caecilians. Be sure the plants are very well anchored. If caves or other such darkened hiding areas are provided, it may well cut down on the burrowing activities of the caecilians. Provide "caves" of sectioned PVC pipe buried for part of their diameter into the substrate.
Short of not being very strongly acidic or alkaline, the pH of the water does not seem particularly important. We suggest that the water be gently filtered. Even with filtering, the tank will need occasional changing.
We have found that the best water temperature for aquatic caecilians is about room temperature – 76 to 82 degrees Fahrenheit.
Feeding
As far as is known, caecilians eat only animal matter. They eat aquatic insects, worms (including earthworms) and other such invertebrates. Captives have also eaten some of the better quality pelleted, sinking fish foods.
They usually feed very well, particularly after dark. Prey is found by scent (and probably by touch). Uneaten food can quickly sour the water. Feed your caecilians prudently.
Handling
Treat this amphibian exactly as you would a fish. Handle it only with a soft, wet net. Scoop the caecilian up in the net and cover the mouth of the net with your free hand to prevent the caecilian from squirming free. Get the caecilian back into the water as quickly as possible.
Medical Concerns
Fortunately for these amphibians, they are largely trouble-free, providing they are fed well, maintained at a correct temperature, and their water is not allowed to sour.
Occasional cases of fungus (Saprolegnia sp.) have occurred when a caecilian has abraded itself on a particularly sharp substrate. These appear as patches of white "fuzz" on the skin of the caecilian.