Caulerpa crapping out, why?

[bigtank]

I have a 70g reef with a fair amount of Caulerpa racemosa in it. About 1/4 of it died and turned yellow today. The rest looks a little yellowish too but otherwise healthy. My water was somewhat murky this morning, but the skimmer seems to have gotten it all. I did get a mat of Poly-Filter and a bottle of Kent Iron for macroalgae.

Is lack of iron the reason for it crapping out? The same thing happened about a week ago. Caulerpa has been in there for over a month and has been harvested in large quantities. I would like to keep it growing fast to pull nutrients out of the water.

???

 

[jdeets]

It's probably going sexual. Remove it when it starts to turn transparent-looking. Otherwise it will disintegrate and all the nutrients it's sucked up in growing will suddenly be released back into the water.

 

[davelin315]

Could it have used up the nutrients it needed in the water and is suffering a die off to a population that can be supported by your system?

 

[reefhope]

As mentioned before the caluerpa is using up the nutrients in the water and will reach a point (if not regularly pruned) where the nutrient level cannot support the caluerpa demand.

I've experienced two rather large and quick(24-36hours)die off of caluerpa due to not keeping it pruned - especially when it starts growing rapidly. You want to promptly remove the dying portion(s) as it will release the nutrients back into the water.HTH

 

[R00]

I too had a lot of caulerpa in my sump. Had to throw out about a gallon of it a week! I started using Phosguard for Po4 removal/maitenence and the caulerpa was gone in a week! I've heard of this happening to others that have used phosguard so it seems like there might be a link between the phos and caulerpa!?!?

Lee

 

[bigtank]

Thanks for the info. How do I get it to grow fast again?

 

[davelin315]

dump a bunch of unwanted crap in your tank and make your water quality bad, then they will come back, but isn't the point to keep the water quality clean?

 

[ging]

"As mentioned before the caluerpa is using up the nutrients in the water and will reach a point (if not regularly pruned) where the nutrient level cannot support the caluerpa demand."

How far back should you prune it ??

ging

 

[Grandczar]

<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote

Caulerpa has been in there for over a month and has been harvested in large quantities. I would like to keep it growing fast to pull nutrients out of the water.

Try dosing with about 5 ml per 100gal of a high quality detergent! This will perk it right up... Along with the added bonus of deceased organisms breaking down into nutrients. But seriously why would you want it to thrive...? Wouldn't that mean it was not getting the job done? Is this a reef tank? or what...?

Surgeon general warning:
pls disregard all information above...
Do not try this at home!

 

[SPC]

Ging, thats another one of those gray areas because of the difference in nutrient loads in each tank. I feel that the amount you prune is the amount that needs to be pruned, if that makes any sense. I too have tried to find an answer for the question you ask, but have come to the conclusion that this is one of those "feel" things for each hobbiest.
Steve

 

[jdeets]

I still don't think caulerpa would just crash like that if it was a nutrient limitation issue. You still have other algae growing. Caulerpa is typically used in refugiums to outcompete other algae forms for nutrients. In a captive system, nutrients are constantly added. I find it highly unlikely that your caulerpa would crash all of a sudden due to lack of nutrients. I'm surprised that this thread has stayed on this course for so long, actually. Nutrient limitation would have the effect of limiting or slowing growth, but not a total, instantaneous crash as you describe.

Based on your description of what is happening, your caulerpa went sexual. That's a common event. When caulerpa goes sexual, it clouds your water, as you described. It also will lose its color.

When it went sexual, it released extra nutrients into the water, and this has fueled growth of the other algaes. IMO the likelihood that your caulerpa crapped out due to lack of nutrients is highly unlikely.

I've got a refugium full of caulerpa racemosa. It grows like weeds. My 'trates are zero, but yet it continues to grow. I harvest frequently. Luckily I haven't had to deal with it going sexual (yet) but it's just a matter of time.

My advice to you would be to get some good softies, and propagate them for trade-in to the LFS. Let the caulerpa do it's job to keep the water quality good for the corals, but don't concentrate your efforts on growing macro. IMO that just sounds a little backward for a reef tank. Just leave it alone and trade it in when you have extra, but concentrate your efforts on cultivating nice soft corals for trade.

 

[naesco]

Your symtoms as jdeets explained indicates that the caulerpa has gone sexual.
Had it been simply a gradual lowering of the nutrients in the tank you would have seen a slowing of the caulerpa growth not a sudden
'crap out' in my opinion (IMO).

 

[bigtank]

I want to keep it growing to sell excess to my LFS, that's the real reason.

This is a reef tank, and I do want good water quality, but I also want to keep enough nutrients in there for the caulerpa to thrive. I still have lots of hair algae on the substrate and some algae on the glass too. Does caulerpa just need more nutrients than other algaes?

 

[bigtank]

Now nearly all the remaining caulerpa is going sexual too. I wonder what causes that. Does this happen in nature? I don't want to lose all of it.

 

[jmeader]

Nearly all causes of caulerpa going sexual have to do with water conditions. It's the plants way of moving to a new location when it finds it's currant location to be unsuitable. The one exception is the required pruning and it is indirectly related to water conditions. When the plant gets too thickly grown, it cuts down on the water flow going through it. You prune it to allow good water circulation through and around it. So you thin it out as well as taking big hunks out. Caulerpa is sensitive to water changes. In particular salinity changes. It will also go sexual if you add too much calcium or buffer additives at one time.

 

[dougc]

I had some feather caulerpa (mexicana?) which went sexual on pretty much a regular six week cycle. I added some razor caulerpa (serrulata) and grape (raceoma). The mexicana pretty much disappeared and the other two types took over the sump. I have not had a crash since. I pull out handfuls every week. You might want to try a different type of caulerpa (or several).