able to keep cichlids with current fish

You Could try Discus Fish as long as you get them from abreeder that breeds them in 7.0 water or neutral water. I keep in my 150 gallon tank Discus, Angels, Ghost Knifes, Blue Rams, Chocolate Pleco, Bala sharks, Pectus Cat, Panda Cory Cat, And Angles. There is about 300 color variations
 
125 litres is what.... 30 gallons? Remember you are restricted cichlid-wise not only by the size of the tank and compatibility to your current fish, but also the diet of the fish and it's water parameters. Make sure any fish you get will suit how the tank is running now. Yellow labs would not. Larger SA/CA cichlids would not. 1 angel is possible, maybe a pair, but you would have to get a small one. Discus are awesome and beautiful fish, but can be picky about water conditions and need very very clean water. I reccommend dwarf cichlids for your current setup. :)

HTH
-Diana
 
bolivian ram, apistogramma ramirezi and paradise fish are small and friendly cichlid. Dont put blood parrot, they will try to eat your guppy as they grew bigger, they are okay only when small, trust me.
 
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