Agreed, my friend...
Let me suggest Chaetomorpha (AKA Spaghetti algae) or Gracilaria (AKA Ogo) as much better choices for algae in the refugium. Numerous aquarists share and enjoy these wonderful species. If you need/want to buy them... two of the many places to find them are IPSF.com and Inlandaquatics.com
With bright light and strong water flow these algae will grow well, fast and stable for you with far fewer concerns about noxious exudations than Caulerpa.
kindly,
Anthony