Any ideas?-i'm stumped......(deformaties)

[paris]

i have this in most of my hiroshima larvae, the larger ones have it....any one seen this before?

 

[ester]

In guppies I'd say it's genetic..
How are you keeping these, perhaps they need more direct sunlight & more calcium? How quickly after hatching do they develop this?

If you isolate one with a deformity, feed it a higher calcium diet & more sunlight, does it disappear again?

Of course, if it's genetic no amount of calcium will help.

Ester