Deformed dorsal fins?

[joz]

On occassion I have had fry growing with either missing or incomplete dorsal fins.
This fish grow quite normally apart from beig deformed and are very healthy.
I'm not sure whether any other have had any similar misfortune but I thought I would check.
Also would anyone know what may cause it and what I should do to stop it happenning again.

[Merrilyn]

Hi joz, if you breed enough fish, you'll always come across a few in the spawn with deformities.

A missing or deformed dorsal fin is pretty common. Can't give you a reason for it happening, and I really don't think there is much you can do about it.

I always cull deformed fish as soon as the condition becomes apparent. Half a dozen or even 10 deformed fish in a spawn of 100 or more is still acceptable, however if you begin getting more than that, then I'd be swapping pairs over to try to correct the problem. If one or other parent continually throws deformed offspring, then I'd stop breeding from that particular fish.

Never, ever breed from a deformed fish, no matter how healthy it appears.

[joz]

Thanks for the quick reply Merrilyn.
At least I know I'm not Robinson Crusoe with this now.
I have no intention from breeding from any fish with deformities either.
Actually I'm not setup for breeding what so ever,but the last instance was in my community tank (fluke). :D
But yep a couple dodgy discus made it. :(