Yes.
Some general information
The worst in terms of toxicity is caulerpa racemosa.
Fish that continually eat unnatural amounts of caulerpa will die.
Stony Coral growth is inhibited by noxious emissions of caulerpa when in close proximity.
Caulerpa produce toxic metabolites that can be toxic in small concentrations to urchin larvae within 24 hours, some toxic to fish within 1 hour.
50% of conchs died within 6 days feeding on Caulerpa caulerpenyne at very high levels.
Most of the toxins are located in the tips of young growing plants and reproductive structures. So the more you prune it the higher levels of toxins get released due to the pruning.
If you can find them, check these studies
Meinesz, Alexandre and Simberloff, Daniel. 1999. Killer Algae.
University of Chicago Press, Chicago. pp. 295-304.
Littler, Diane Scullion and Littler, Mark Masterson. 2000. Caribbean Reef Plants.
OffShore Graphics Inc, Washington, D.C. pp. 356-380
Hashimoto Y, Fusetani N, Nozawa K.
Screening of the toxic algae on coral reefs. 569-572.
Anjaneyulu ASR, Prakash CVS, Raju KVS, Mallavadhani UV. 1992.
Isolation of new aromatic derivatives from a marine algal species Caulerpa racemosa.
J Natural Products 55(4): 496-499.