Coral question help!

[jordsy]

ok hopefully this pic worked
This coral keeps sheding all its limbs. Hes still extended fully in the day and looks very healthy but keeps loosing limbs. Ive been putting the frags in my live rock and they seem to be doing fine....

I have little trace amounts of nitrate, nitrites, phosphates. ph 8.0, salt 1.024, temp 80, no ammonia, calcium 460 ppm....

I thought it was just reproducing but its getting outta hand now
any suggestions?