Sexing my blue lombardi cichlids

[cichlid7646]

I realy need to sex my blue lombardi cichlid so i can get rid of the males before they kill the females. They are about 5 months old now and are starting to change in colour. Tho of them are larger (about 5 cm) and are a pale blue with faint greyish stripes. The other two are smaler (about 3.5 cm) they are the same pale blue but have much darker stripes.

 

[Freakgecko91]

Makes turn yellow. The stripes are not as relevant to second these. It’s pretty obvious when you have a male. If they’re all blue, they’re either all female or still too young to sex. You can always vent then, however, that is not my expertise