The eyeless, troglomorphic form is found only in Mexico but this species is in fact widely-distributed from the southern United States of Texas and New Mexico, through Mexico itself and into Guatemala.
Being blind, the fish does not require any specific decor or form of cover, and can be kept in most types of setup. Plants are not harmed, as obviously they don’t feature in its natural waters. Alternatively, you could choose to organise a cave-style tank for it, with tall rocks or slate pieces placed along the back and sides of the tank, smaller rocks in the centre and a dark substrate.
Hardy and peaceful, it’s actually an excellent choice for the beginner and suitable for most community aquaria, though very shy or sluggish tankmates are best-avoided. It sometimes nips at tankmates when feeding, but this is more attributable to its searching technique than aggression. Although it can’t be described as gregarious it doesn seem to fare better when maintained in a group and we suggest the purchase of at least four individuals.
While the surface-dwelling form of this species is fairly unremarkable and rarely-seen in the hobby, the blind form is very popular indeed. The two may have diverged as recently as within the last 10,000 years, with the blind form losing its eyes and much of its pigment. This probably happened because the fish needed better development in other sensory areas. Losing unnecessary and energy-consuming aspects of its physiology allowed it to devote more energy to? developments such as increased numbers of taste receptors on the head.
It uses its lateral line to detect small changes in the water pressure around it, allowing it to navigate and find food. Interestingly, if it is placed in a new environment containing objects it does not recognise, it will increase its swimming speed. This is thought to increase stimulation of the lateral line, allowing it to absorb information more quickly. It is now known that the fish actually produces a detailed spatial map of its surroundings which it memorises quite quickly.
What We Like About This Fish:
- Peaceful and hardy addition to tanks , though they cannot tolerate the extreme cold conditions that some other Fish varieties can inhabit
- Very active
- Unique appearance as well as plenty of personality.
CARE GUIDELINES:
- Diet: Omnivorous, should be fed relatively low-protein foods designed specifically for goldfish
- Social behaviour: Socialy active
- Very active
RECOMMENDED TANK PARAMETERS:
- pH level range: 6.0 – 8.0 (flexible as long as sudden changes are avoided.)
- Temperature range: 65° - 72° F (18° - 22° C)
- KH: 5 - 19 dKH
- Minimum tank size: 30+ gallons for a juvenile or subadult, though larger tanks are much more optimal. This fish should be given the largest tank with best filtration possible.