Hey here is some information on Goby's.
With almost 1900 described species and estimates over 2000. The family is one of the largest families of fish. Generally not commanding high prices in the aquarium trade, these fish are extremely popular among aquarists fo a variety of reasons including their generally small size, their interesting behaviours and their high tolerance of aquarium life. While there are species that reach close to 50cm, the vast majority grow to less then 10cm long and most that are popular in the aqaurium trade fall in the ranges of about 3-15cm. The smallest known vertebrate species belong this family.
In the aquaium trade, the name goby is not restricted to species within the family Gobiidae. Many fish from closely related families including blennies, dragonets, clingfishes and dartfishes are reffered to as gobies and while this is not a huge issue, there are instances where husbandry related characteristics are incorrectly placed on particular species. A prime example of this is the ready generalization that gobies will readily accept a variety of prepared foods. While this is not true for all species, it is an overall fairly true statement. Two species of dragonet are commonly sold as "mandarin gobies" and the resulting implication of the average aquarist is that these fish will behave and invariably feed like most other gobies, the end result is often a starving and eventually, dead, fish.
With few exceptions, gobies are carnivores, feeding primaril on
zooplankton and in the aqaurium should readily accept a wide range of foods including
brine shrimp, mysis shrimp as well as most prepared dry foods such as flakes and pellets. As mentioned this is not true for all species. There are a number of "sand-sifting" gobies, primarily from the genus Valencienneia as well as the commonly available Signigobius Biocellatus, which naturally feed on inverterbrates that live within the upper layers of the substrate such as worms and small cructaceans. In the aqaurium, these fish continue their behaviour of sifting sand to find their pray which given a healthy sand bed results in removable of valuable sand bed fauna and eventually a removal of all available food items. This often leads to the demise of the individual unless the fish can be trained to take alternate food items. This can be achieved by placing food items such as frozen mysis shrimp or pellets in the sand to get the fish accustomed to feeding on these food items, over time the food can be simply dropped on the surface of the sandbed and eventually the food may be taken directly from the water column as the fish associates the object as food. One of the few groups that are more omnivorous are the hover gobies of the genus Amblygobius. These fish will graze on micro algae as well as feeding on small inverterbrates amongst the rocks.
Sorry If this is in the wrong forum section but i couldnt find a goby section anywhere so maybe we need one
Hope This Helps You
-Matt
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