"Paul" wrote in message ...
Other than mollies can other freshwater fish be compatable in a sal****er
marine reef tank

Mollies are not really freshwater... they are brackish water fish.
From the all brackish water fish they are the cheapest, so here is
the reason for popularity...
I am sure many typical brackish water fish can be adopted to full
strenght sal****er environment, but why would you like to do it?
They are used to take big salinity fluctuations but living long time
in fresh or fully sal****er most definitelly shortes their lifespan.