There are many, many factors that determine whether two animals can live in the same tank.
All fish, corals and inverts have their own unique personalities which will affect how compatible they are with others. The length of time your tank has been set up, the order in which your current inhabitants were added to the tank and the number of hiding paces / zones in your tank will also affect how two animals will get along.
Obviously we can't know the personalities of your fish or the intricate details of your tank, so we just use the typical animal from each species when determining compatibility.
There are hundreds of charts out there that aim to help you with compatibility issues but all of the ones we have seen compare families of fish rather than individual species. They all say that a goby and another goby are compatible 'with caution'. There are hundreds & hundreds of combinations of gobies and most of them can happily live together in the average tank. However, because a few gobies shouldn't be kept with other gobies, this entry in compatibility charts is generally set to 'with caution'.
Most of our compatibility results are taken directly from the standard compatibility chart however we will mention when an 'override' has been put in place.
Each compatibility page also allows you to vote as to whether you think two species are 'compatible', 'compatible with caution' or 'not compatible'. You can also see how other visitors to the site have voted.
No matter what result our guide or any compatibility chart gives you, you must check with you LFS before making a purchase!!