I'm sure most hobbyists that have kept
Caulerpa in their refugium or display tank know about or have
experienced this algae's reproductive activity. "Going
sexual," as we all like to call it. This has happened
to me as well. I have had the displeasure of waking up to
a cloudy tank three times in the past, and I assure you I
definitely know what a mess it is to deal with. However, this
time, I happened to document the events leading up to the
event with some photographs. These photos clearly show some
warning signs of the imminent sexual activity. Distinctive
and noticeable changes take place in the algae prior to the
release of the spores. Upon noticing these changes, a bit
of quick action can head off the potential problems of sporulation.
Figure 1. This picture shows the gametangia formed
on the thallus of the Caulerpa.
Figure 2. A close-up shot of the gametangia.
The night before the last time my Caulerpa
released gametes, I noticed something strange on the alga
and decided to take some pictures so I could ask Ron Shimek
about it the next day. It turned out that I should have, instead,
"gone to town" removing that alga because I woke
up to a cloudy mess in the tank. In running around and replacing
carbon Polyfilters® and preparing for water changes, I
totally forgot that I had taken photos the night before. After
I had caught up and decided to catch my breath, I remembered
them and decided to look at them and post my question. It
turns out that I captured some changes in the alga that were
distinctive and can probably be used to forewarn of any future
"Caulerpa orgies." My pictures serve as a
warning to pay attention to your Caulerpa and if something
similar to what I've seen is found, be sure to act quickly.
I would suggest removing all the alga, as that individual
or "bunch" will go sexual once the gametangia are
formed, no matter what one does. Once the nuclei begin subdividing
and form gametangia, the thallus, or main body of the alga
will release spores and die regardless of what is done. Earlier
pruning of the alga may delay or prevent gametangia formation.
However, from my experience with the process, it is apparent
that it cannot be stopped simply by removing part of the algae,
once the gametangia have begun forming.
Figure 3. A view of the tank the morning Caulerpa
serrulata went "sexual."
Figure 4. A close-up view of the Caulerpa after
sporulating. Note the
discolored thallus of the algae that had released the spores.