Now you're starting to sound like doug!

I thought that the fish wasn't that picky after reading this:

Desert goby
Chlamydogobius eremius

The desert goby has three particular adaptations to the mound springs in its tolerance of a wide range of salinities, fluctuating temperatures and varying oxygen levels.

The desert goby eats almost anything—algae, detritus, small insects, crustaceans. Its good sense of smell helps it locate food and it feeds at night. It settles into silt, under rocks and in weeds, to hide from predators and avoid extreme temperatures although it can tolerate temperatures of 5–40¼C (41F-106F!!!). As a last resort it will emerge from the water to take advantage of evaporative cooling. When oxygen levels in the water are low it will "gulp" air (aerial respiration). The desert goby will also position itself above photosynthesising algae to catch the oxygen produced. It can also withstand large and rapid changes in salinity if the pond reduces in size because of evaporation. The ventral fin has a sucker to anchor it to rocks in fast flowing water but it can be dispersed during floods to new locations. It can also establish itself in artificial water bodies such as dams.

The female lays up to 250 eggs, often under rock overhangs and the male guards them. The desert goby can change colour rapidly to blend in with the background.

from Desert Refuges

After reading that they seem to be like guppies. Add water, food, and sit back to wait for babies.

Kind of like the perfect fish for people who don't pay attention to their tanks often. 41-106F, kind of hard to freeze/cook them in a house. Salinity is.....well who cares right? Just as long as it's not the Dead Sea.