I have 3 Clowns, had the first one for 2-3months but the other two for 2-3 weeks...
It was a little risky to put them together but it worked! They were aggressive towards each other the first night but are getting along fine now.
The first one stays in the left corner of the tank behind plants and the other two always together in the right corner
They are about 5" and growing fast...
Opposite to what most other say about their CK´s, mine dont eat feeders.
I only give feeders to the Needlenose and those who escape him hide on the bottom and are not bothered by the Knifes

Im happy they dont eat feeders as that would be extremly expensive on the long run.
I feed them frozen shrimp, earthworms, lambheart, frozen fish and they love catfish pellets (waiting on my order of carnivour pellets)
Here is a pic of them 3, have to get better pics: