911

[Tom Owens]

Folks, I hate to make my first post here an emergency, but I really have no choice.

Long story short: I just started, after a 10 year hiatus, a 29 gallon nano reef. Everything has been going just fine...until just this past Sunday. I added a small clump of Halmeida. (Spelling?) Everything looked great until I got home today. All my corals were drawn in like something was bad wrong. The Halmeida was damn near completely white. I yanked it instantly. I've got my 5 stage RO/DI unit brewing water for a 50% water change.

All of my peramiters test perfectly with the exception of KH. It's a bit high. Oddly, my PH is still a perfect 8.3. I don't get it. What could have happened that made my corals (Star Polyp, Yellow Polyp, Galaxia, Trumpet and an unidentified shroom) go totally south?

Perameters:
PH: 8.3
Nitrate: 0
Nitrite: 0
Phosphate: .05
KH: off the scale (Literally...it took 13 drops to turn the mixture yellow. It only goes to 12)
Ammonia: 0

I'm totally stumped on this one. Any help at all would be greatly appreciated.

Thanks in advance,
Tom

[inwall75]

Tom,

First off....WELCOME TO 3REEF!!!

What could have happened that made my corals (Star Polyp, Yellow Polyp, Galaxia, Trumpet and an unidentified shroom) go totally south?

KH: off the scale (Literally...it took 13 drops to turn the mixture yellow. It only goes to 12)

Your instincts are right. BIG water change. Both of the above issues were caused by the sporulation of your Halimeda. Not only is Halimeda holocarpic where the entire plant becomes sexual, it's "goes sexual" in a synchronized fashion. In other words, if one Halimeda plant goes sexual, every single Halimeda plant in the tank will go too.

I don't know if you have a sump or not. If you do, run granular activated carbon as well. After you do this 50% waterchange, keep making water so you can do another one tomorrow. The alkalinity issue is due to brand new sand being produced that is not coated with organics so for a change, real chemical exchanges are happening. (Most people don't know how much of the worlds sand is made by Halimeda).

I'll retrieve some info that will explain this in more detail in a bit. I just wanted to post quickly so that you will know you're on the right track.

[chrisANDbarb]

i agree with Curt, water changes and carbon

[inwall75]

Ok....Here's a little more detail.


The following quotes are from: Halimeda: The Cactus Algae by Kirby Adams - Reefkeeping.com

Halimeda go a step further to ward off aragonite-munching herbivores, such as parrotfish, by synthesizing noxious and potentially toxic secondary metabolites. The aptly named halimedatrial and halimedatetraacetate are diterpenoid compounds that appear to give Halimeda an extremely noxious taste and could prove toxic in large quantities (Paul and vanAlstyne 198.

These secondary metabolites (toxins, chemical warfare, etc) appear to be quite toxic to corals too. However, there's also the possibility of greatly lowered dissolved Oxygen.

Here's a buddies SPS prop tank after his Halimeda did this to him. This is Tom's 180g tank after not before 2 separate 90% waterchanges. (Mind you, he had a lot of Halimeda so hopefully you won't have this amount of difficulty with just a little bit).

Regarding the algae reproduction.....When Halimeda reproduce, the whole plant becomes reproductive at once....they are called holocarpic. Prior to the algae releasing its gametes....it turns pale white and has dark green dots (the gametangia).

Halimeda's sexual reproduction is similar, but with the added benefit of a known warning indicator. Hours before releasing gametes, the algae will turn pale white with dots of very dark green or almost black along the edges of the thalli. The dots are called gametangia and contain all of the contents of the living plant, concentrated in tiny capsules. This creation of the gametangia is called sporulation. Shortly thereafter, the gametes are released in a fashion similar to Caulerpa's. Plants that reproduce in this fashion, with the entire plant becoming reproductive, are said to be holocarpic. These sexual events have been blamed for sudden deaths of tank inhabitants, and the secondary metabolites of the algae are often fingered as the cause.

Here's another source: AIMS - BIG BANK SHOALS OF THE TIMOR SEA - Halimeda ecosystems - Reproduction

Recent observations have shown that sexual reproduction in Halimeda plants is to some extent synchronised (Clifton 1997, Hay 1997). Many individuals in a population may become fertile within a period of only a few days, and sometimes on the same day. Synchrony can be so exact that fertility events have been observed to occur simultaneously in the field and in a laboratory aquarium (Drew and Abel, 198.

[bouraganes]

Hi Tom , it is good to have you here and I wanted to say how sorry I was to hear about your tank.You certainly came to the right spot for help, there are plenty of helpful and knowledgeable people here ( such as inwall75) who are more than willing to help you thru your dilema(s). I am always browsing these forums and I glean alot of good info - for example I almost bought some of that stuff the other day, I wouldn't have thought such an innocent looking plant could cause so much trouble. Stick around read and learn with the rest of us- we can all help each other!

[inwall75]

It's all a matter of degrees. A clump of Halimeda sporulating in an unskimmed nano is an issue. A clump of Halimeda sporulating in a 75g with a skimmer is no big deal. As my friend found out, a whole lot of Halimeda sporulating can be a big deal in even a large tank like a 180.

[Tom Owens]

Thanks large, folks. With the Halimeda gone (I chunked it completely.) The tank is already looking better. The fact that it's only a 29 nano makes it worse based on the info given. I'm prepping up another 12 gallons right now to do a second change.

Again, thanks a million.

Tom