Well, for example, if you are talking apistos, shell dwellers, rams, small julidichromis, and even brichardi "daffodils", etc. you are generally fine. I've even bred daffodils and nanochromis parilus and multies in five gallon tanks. Who hasn't bred even convicts in a ten gallon! (They would probably breed in a coffee mug). But if you use a broader definition of "dwarf cichlid" that many folks do to include kribs, jewels, "dwarf" mbunas, leleupi, etc. then you start getting in trouble. The bottom line is (especially for cichlids) how territorial is a particular species and how large is that territory typically deliniated. There will always be exceptions, so it is better to go on the conservative side and only include the smallest, most peaceful species for a 10 gallon set up. And, for many, rock work/caves, etc. are more important than plants.
