suggestions for a 75 g tank

[syddakyd]

well for one i would recomend mollies only for brackish-marine aquariums.

tiger barbs wont really bother a gourami, if anything the gourami might chase them a little.

only one red tail or rainbow shark per tank unless it's alot larger.

 

[Lupin]

well for one i would recomend mollies only for brackish-marine aquariums.

A lot of mollies have been accustomed to freshwater environment despite the fact that some of them do well in water where salinity is high.

tiger barbs wont really bother a gourami, if anything the gourami might chase them a little.

If this was your experience, obviously it'll not be the same for another. A warning beforehand is better than assuming that it will or will not work at all.