Yesterday, a quite large Tridacna maxima started to release sperm at 8pm.
The other clams (2nd large T. maxima, 4 med. T. maxima, 3 large T. derasa) joined in.
30 min later, they stopped.
After a short break, the large clams started to release eggs.
30 min later, they stopped.
It took the reef an hour to have clean water again.
Unfortunately no larvae will survive (UV/filter/coral/wrong sperm:egg ratio)
This happens at least 3 times a year, usually triggered by environment changes.
This time, I changed the one year old 4*400Watts MH bulbs two days prior to this event.
Lucky me, that the cam was ready.

This is what the reef looks like today.
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