I added caulerpa to display tank (photo)

[tippytango]

I have the same problem with my new Caulerpa. In addition it was eaten by some worms and slugs. I have removed quite a few of these. The leaves are turning white overnight. It seems the die off may be slowing down as a new leaf appeared. I do not know if it is the acclimation to the new environment, the severe attack by worms and slugs or the lack of nutrition that caused it. I do not have any fish in that tank, I just transferred the water from my FOWLR tank. I will follow to see if you solve your problem. The red macro are faring better, but yes a lot of the red grapes fell off.

My caulerpa is looking all better! No more whitening and I’m getting some new growth. I already see why I am going to have to stay on top of trimming it back! I am loving the look of these little palm trees in the tank.
My red grape botryocladia is looking unchanged. Which I suppose is a good thing… once it’s settled hopefully it will start growing in.
How are yours doing?

 

[Nemo&Friends]

I am not sure of what to think. My Caulerpa grows a new leaf, but at the same time has one turning white... so weird. The red grapes is stationary too. I added a young FW molly, from my FWT in the tank with the red grapes algae to see if the added nitrate would help, as I did not have fish in it. The molly did not have any problem acclimating to Salt... and started grazing on the "bad" algae on my glass immediately. I will see if it helps the"good" algae.
I want my caulerpa to grow fast, as I want to give the trimming to my Foxface.

 

[tippytango]

I am not sure of what to think. My Caulerpa grows a new leaf, but at the same time has one turning white... so weird. The red grapes is stationary too. I added a young FW molly, from my FWT in the tank with the red grapes algae to see if the added nitrate would help, as I did not have fish in it. The molly did not have any problem acclimating to Salt... and started grazing on the "bad" algae on my glass immediately. I will see if it helps the"good" algae.
I want my caulerpa to grow fast, as I want to give the trimming to my Foxface.

So, in regards to your caulerpa mystery… I could compare it to some plants in my garden which, when exposed to more sunlight than before, the existing leaves will brown while new growth will be adapted to the extra sun exposure and not brown. Maybe same kind of thing is happening to your caulerpa! Who knows! I bet as long as there’s new growth it should be all good! But sounds like you have A LOT more aquarium experience than me