Caulerpa brachypus problem

[acer]

Looking for info on getting rid of this in my tank. It has overgrown and is very tough to get off of rocks. It has overgrown and has smothered my Xenia, Zoa's and other smaller corals. Nothing so far has eated it- including a Yellow tang. I would hate to have to pitch all the rock and start over. Have confirmed ID by a fellow refer and LFS. Help please...

 

[Samala]

Very interesting, we dont often hear of this algae taking over a system. If you use scissors to prune it off the rocks, does it grow back? I had the hardest time establishing this for culturing purposes, its hard to imagine having it invade. Then again, if the right conditions are present..

Are there other types of algae in this system to compete with the Sargassum for nutrients? It might help contain its spread. Perhaps a fuge of Chaetomorpha? Or in an FO you could use other types of algae as well.

>Sarah

 

[acer]

Yes- have had refugium with cheato from onset of system= 9 months ago. Cheato is healthy- but not proliferating well. I am no expert on the ID aspect- looking around the web I came across a picture of Cauleerpa Brachpus- it sure looked like what I have- but I could not enlarge the picture enough to know for sure. The closest Sargassum picture that looked like mine that I found was a Halophila ( family Hydrocharitaceae). My digital will not take close up very well. Water= RO , but the system is not great= TDS=26-30. So, I do have some extra organic nutrients with a slight phosphate reading- but in tolerance range according to the Aquarium Phamaceuticals test kit= between 0.0 to 0.5

 

[Samala]

Ah, so its not a Sargassum species algae, but rather a species of macroalgae or seaweed, an unknown one. The Halophila are seagrasses, and I don't know of anyone who has had them invade from seeds into their reef tanks. They are typically purposely introduced and then greatly coddled to ensure they thrive.

It is most likely you have a species of Caulerpa, a green seaweed or macroalgae. Caulerpa brachypus is very small in size, but has small serrated leaves, about 1-2" tall. The larger version of this is Caulerpa prolifera, or blade Caulerpa, which is typically 4-6" in height, long blades that are dark green.

I can see now why you've had trouble removing it as the Caulerpas have very fuzzy rhizoid material, or roots, which really latch onto porous substrate.

It is important to try to keep the population or overall biomass of this algae down. If it reaches a point where it runs out of nutrients it may sporulate (or go sexual) and release the spores, toxins and other things from the cell into the tank. Enough of this can kill or damage the fish.

Do you have any herbivores in this system? There is only one specific predator of Caulerpa that I know of, it is a species of sacoglassan (sp?) nudibranch, and are not very common in the hobby. Some tangs and rabbitfish will eat Caulerpa with relish though.

>Sarah

 

[acer]

I am not sure what it is - going by ID from others. THe LFS and a Fellow reefer did think it was a type of sargassum, but pics I have found on the web all show Sargassum as brown and large leaved with "pods" . My "plant" has very thin branching "vines" that climb and stick to the rock and plumbing (does not grow on sand or glass) with small leaves ( in pairs) coming off the vines and is green , not brown. Wish I could take a good pic and post it , I will try again tomarrow. THanks.

 

[acer]

OK- definetly think this macro is Caulerpa Brachypus. Pics and description are pretty conclusive. Allright you "experts" - all kinds of web articles on how invasive/toxic/etc. this stuff is. Do I take out all the rock - if so- How do I kill the plant yet beable to re-use the rock. Help please!!!!

 

[Skipper]

Changed the thread title...

 

[acer]

Thanks for the change Skipper- have been doing some reading and this type of caulerpa is killing some of the Florida reefs. So, it is very aggresive and nothing much eats it. SO, I guess I will just take out the live rock and let it dry out in a dark place to kill the macro on it. Then "cook" it .

 

[Skipper]

Not even an urchin will eat it? That's odd.

 

[acer]

I had a long spine black urchin - but he just ate the coralin algea off the walls and grew way to big for a smaller tank like I have. So I traded him in.

 

[piercho]

IME, Chaetomorpha does not compete well with some Caulerpas. For me, Chaeto production shut down and the Chaeto eventually disappeared in my veg filter while C. peltata continued to grow well. IME, some Caulerpas like peltata can compete very well for nutrients in a low-nutrient environment. If the reef tank is a better enviroment for nutrient uptake than the vegetative filter (brighter light, stronger circulation), the available nutrients will be bound in the reef before they ever make it to the veg filter.

As far as grazers, IME Diadema (long spined urchins) don't graze some Caulerpas. Siganus (rabbitfish) may be a better bet, but this is a larger fish as an adult. There are specialized grazers of siphonous green algae in the sea slug family. I have not ever used these and they don't seem to be common in the hobby.

Aggressive manual control by removing the rock from the tank and wire brushing it has worked best for me. Other people have suggested using a pressure washer. If you would be destroying coral encrusted on the rock by doing this, your choices get harder.

 

[acer]

yes- i will loose some more Zoa's, a few Rics, and hairy mushrooms that I know I cannot get off my rock. Oh well, prefer to loose a few more now- rather than constantly fight this and loose Acro's, etc later..

 

[Macroculture]

Sometimes you can switch out the Chaetomorpha in the refugium for Caulerpa instead. This can help if you just want to try to starve out the Caulerpa in your main tank. A good amount of C. taxifolia or C. racemosa can compete effectively for nutrients with many other types of Caulerpa. That is one reason why it can be diificult to grow multiple species of Caulerpa in the same system. Caulerpa is not always the best bet in a refugium, but some people use it anyway to help control or prevent outbreaks of nuisance Caulerpa in the main tank. The only other option I can think of to avoid losing the life on the live rock is to try to see if you can find some sacoglossan sea slugs like Elysia subornata to help control the Caulerpa.