Royal clown knife mouth size?

[Omrit]

I have never seen a RCK above 20 inches in captivity so assuming that is about the size they are likely to stay around what can one that size swallow?

How many inches does a standard shape cichlid (like a firemouth) need to be for it to be 100% safe with it?

Not finding much data on the RCK or the regular clown knife other than "mouth is bigger than it seems".

 

[tlindsey]

How many inches does a standard shape cichlid (like a firemouth) need to be for it to be 100% safe with it?

Have you ever seen your clown knife yawn?
Your firemouth would have to be very large over 5 inches.

 

[Omrit]

Have you ever seen your clown knife yawn?
Your firemouth would have to be very large over 5 inches.

I don't have the knife yet nor do I have any firemouths it's just the most cichlid shaped cichlid I could think of. I think I want a RCK eventually, but I wanted to plan ahead with tank mates.

So a standard shaped fish over 5 inches is safe with all but the largest RCK correct?

 

[tlindsey]

So a standard shaped fish over 5 inches is safe with all but the largest RCK correct?

Yes

 

[SourAngelfish]

I’d say a 5” or so firemouth would be safe with most, I have my royals with some 4-5” fish right now. A full size adult could probably cram a fish up to 6” though.

Out of the genus, ornata and blanci appear to be the most piscivorous, especially when looking at jaw structure. Because of this I’m far less trusting of them with fish. The other species seem to ignore fish if other foods are available though