Caulerpa Is Turning White In Some Places?

[SkiFletch]

If the UV were powerful enough, yes. But we're talking like commercial sized UV here...

 

[Donya]

What if does release some (doesnt melt, but releases some spores) and it "attacks" your main tank. Don't forget this is a rooting macro algae, next, its one of the least commonly eaten macro algae, if your tang etc. eat it, great, basically you got lucky. Manual removal, good luck removing it all (including the roots) without releasing any spores.

By "attacks" it sounds like you mean what Chaeto did to one of my tanks. Yes, even Chaeto can be a bear to remove. I never did win that battle until I broke the tank down to move to a new house.

Just like other, more complex plants, there are good ways and very bad ways to prune Caulerpa. Ripping it out is the worst way to go, particularly if you snap a main stem. That will stress the plant and cause fluid loss, which can trigger spores as already mentioned. The method I have had the most success with is time-consuming but highly effective for removing large portions: tie off the section at the main stems and leave it for a bit. When the stem has clearly started to pinch itself off on either side of the pressure, it's safe to cut. Sometimes it's as fast as pinching it by hand for a few minutes and then breaking it.

Also, just like other plants, you can't put a macroalgae like Caulerpa in a display tank and expect to step back and ignore it thereafter. It will require regular maintenance, just like freshwater planted tanks require to prevent overgrowth when nutrients are abundant. Caulerpa is not for the lazy aquarist.

Do a google search (razor caulurpa), the third link, read it. Some people who were unlucky enough to have it in their main tank, possibly through refugium spores, or simply putting it in the main tank.

Well, although I can't pull the link up offhand (I'm having some weird issues with IE crashing on me when I try to open 2 windows at once), I found somewhere after the 3rd link a thread of people complaining that razor Caulerpa was overrunning the tank and fish weren't eating it, etc. I'm assuming that's the one you were talking about since the other linkes I saw were places to buy it. Again, that thread sounded to me like a case of not nipping the situation in the bud through early maintenance. I made similar mistakes when I first ended up with Chaeto, but headed it off in other tanks after my first run in with the problem.

To wrap it up, cheato is a much more efficent nutrient exporter in terms of space, their dry weight is much higher, and they require less space.

I will agree there for most cases. I would argue with razor Caulerpa...lol. The only way Chaeto ever out-competed it was by choking it out further down and preventing it from growing properly. Other than that, I kept seeing Chaeto get out-competed by that species, which would tend to suggest that the razor Caulerpa was the more efficient exporter. That's definitely not been the case though for other Caulerpa species I've kept.

EDIT: And i do recall the OP talking about red caulpera, not razor.

I brought up razor Caulerpa to point out the problems of trying to lump all Caulerpas into one bucket as far as their relative hardiness and responses to normal tank conditions, since most of the tales of woe I've heard regarding thing like the entire tank's worth going sexual at once stem from only a few species and aren't necessarily applicable to others.

If the UV were powerful enough, yes. But we're talking like commercial sized UV here...

One of the LFSs I used to go to had a UV stuff set up on one of their tanks like that, and it hadn't stopped little bits of refugium algae from cropping up elsewhere in the tank. Sometimes little fragments of macro can also get sucked up by a pump and spat out elsewhere to establish new growth, and I'd be pretty amazed if a quick trip through a UV sterilizer would nuke fragments like that.