Is that a 24 litre or a 240 litre? 24 is only 6 gallons which is much too small for either of the two species. 240 is 60 gallons and should be fine provided the kissers grow quickly so that they are at least equal in size to your gold. If it's a female, it'll eventualy calm down over the next few weeks provided your kissers can hold their own. If male, you could have some serious trouble if the kissers aren't at least the same size as him. BTW, the kissers will eventualy grow to about 8" and should then turn the tables and become the dominant ones.