Looking for imperfections in clownfish

At what point in time do you begin looking for imperfections in your clownfish fry? I would like to hear different protocols from the breeders that cull their fry.

You can pick you crooked backs pretty quick - just after meta.  I usually do a cull at around 15 days where I get rid of the crooked backs.  I do another cull of anything I can see when I transfer to growout at around 30 days.  I catch most of them at that point.  I find it takes longer for pinched heads to become recognizable, probably around 3 months or so, but maybe I'm just not great at seeing that deformity yet.

Don't let fear and common sense stop you! =]

I haven't been successful at getting any of my fish to spawn yet (let alone get to the point where I need to cull lol) but is there a good place to read on what deformities look like and which should be culled?

I haven't come across anything like that...maybe just Google each deformity?
 
Crooked/bent backs
Flared gills
Pinched heads
Missing fins (usually pectoral)
Incomplete gill covers
Blunt nose 
Underbite
 
What else?  All I can think of right now.

Don't let fear and common sense stop you! =]

You might find this article in Reef Hobbyist Magazine useful http://www.reefhobbyistmagazine.com/archives/vol_5/issue18/pages/24.htm

Thank you very much for the responses!

On average, what percentage of your fry does everyone end up culling? Really curious to hear some answers.

I've had very good luck and only needed to cull a few over the years. Usually weak ones just don't make it to settlement but I did have one really bad Picasso that lived quite a while...

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