hi i have a 20 gallon aquarium with zebra danios serpae ,pristella and black tetras . also a corydoras ,platys swordtails and two pearl gouramis maybe yall could give me interesting suggestions i was thinking about silver dollars and maybe an orange chromide cichlid but maybe yall got better ideas than me kkeep in mind that i cant get anything too agressive but my fish are all pretty active and capable of defending themselves see ya