What are we missing?

[smallblock]

Somethings been bothering me for a while now. A little while back I was reading about RODI water and if it were safe to drink. I came across a guys response that said Rodi is the cause of some of our SPS to be brittle. The more and more I think about it the more it bothers me. Why are our corals so brittle? For instance my birdsnest snaps if you stare at it for too long. I cant imagine a birdsnest in the wild being this brittle.

What I want to know is what are everyones opinion on why some of the corals we keep are so brittle. Is anyone using natural seawater? IF you do, do you notice a difference in this area. Could it be that some of the trace elements are missing and this is the cause?
I could be totally wrong and that how they are supposed to be but my gut says otherwise.

All comments and debate are welcome.

 

[cr500_af]

I'll jump in... I don't see RO/DI being a cause, since our end product is as close to NSW as we can make it... the idea being to remove EVERYTHING but H20, so that we can put back exactly what needs to be in there with our salt mix.

This is not something I tested, but I was warned the first time I dove on a reef that the stony corals were fragile and not to touch them... so, exactly how fragile I would only be able to guess at.

Off the cuff, I'd look at a correlation between low vs high CA numbers as being a possible factor rather than how the water is purified. That is just thinking out loud, though, so I'm sure somebody will come along and tell me I'm wrong.

 

[vicbay]

i read somewhere that it was relative to current. what flow we produce in our tanks is no comparison to natural waters. therefore the coral's structure is stronger due to necessity. sounded good to me lol

 

[smallblock]

I also was reading in coral magazine and they were talking about the element the chemist focus on and we call essential, they touched on there are 74 or something trace elements in natural seawater that we dont use in the aquaria setting

Edit: elements*

 

[insane_reef_keeper]

Smallblock;638247 wrote: I also was reading in coral magazine and they were talking about the element the chemist focus on and we call essential, they touched on there are 74 or something trace elements in natural seawater that we dont use in the aquaria setting

Edit: elements*

What are those elements? Are there any manufacturers out there that have consolidated those elements into liquid form for our reefs?

 

[lifestudent]

vicbay;638244 wrote: i read somewhere that it was relative to current. what flow we produce in our tanks is no comparison to natural waters. therefore the coral's structure is stronger due to necessity. sounded good to me lol

I totally agree! :yes:

For SPS, they need lots of very random flow to have thick stalks. I've read 40 to 70 times turnover is a good start for SPS that are on the reef crest! Many of us don't come anywhere near that!

I spoke to Jorge at Pure Reef last year about this same issue and he had the same observation: heavy flow produces thick branches. Thin, brittle branches are normally the result of too low to too little flow.

Dana Riddle wrote an article in this year's

 

[acroholic]

Smallblock;638232 wrote: Somethings been bothering me for a while now. A little while back I was reading about RODI water and if it were safe to drink. I came across a guys response that said Rodi is the cause of some of our SPS to be brittle. The more and more I think about it the more it bothers me. Why are our corals so brittle? For instance my birdsnest snaps if you stare at it for too long. I cant imagine a birdsnest in the wild being this brittle.

What I want to know is what are everyones opinion on why some of the corals we keep are so brittle. Is anyone using natural seawater? IF you do, do you notice a difference in this area. Could it be that some of the trace elements are missing and this is the cause?
I could be totally wrong and that how they are supposed to be but my gut says otherwise.

All comments and debate are welcome.

Birdsnest is a thin branched coral. Thin branched seratiopora corals and Echinata type corals are delicate by the nature of their form. I have other corals you'd have to take a hammer to to break any off.

Have you ever seen a brittle thick branched coral? I haven't. I just don't think we can generalize a trait we see in one coral to all corals. More factors involved than just that.

How easily a coral breaks may also be a part of it's reproductive strategy. If a fish or something hits it and breaks off a piece, it sinks and may grow into a new colony where it lands.

 

[mapleredta]

I have a ORA stylophora coral and it's a *insert appropriate swear word* to frag.

 

[acroholic]

vicbay;638244 wrote: i read somewhere that it was relative to current. what flow we produce in our tanks is no comparison to natural waters. therefore the coral's structure is stronger due to necessity. sounded good to me lol

I think this is true relative so some species, but not all. Birdsnest for example. I have not seen thicker branches in it resulting from strong flow. It is thin branched no matter what flow it gets, IME.

 

[jennm]

I've seen better, thicker growth in some branching LPS corals when tanks are dosed with calcium, magnesium and trace elements.

A number of years ago I sold a branching frogspawn to a customer who meticulously dosed these things. As time went on, they got a bit more "relaxed" and pretty much stopped dosing. The corals continued to grow, and thrive, but not quite as well.

When they took their tank down and brought their stuff in to me, I observed that the older skeletal growth on the frogspawn was very thick and dense. So much so that cutting it to frag it was rather difficult. However, the top portions of the skeleton - more recent growth, was thin and very brittle - we could break it with our hands quite easily. The coral did grow but as time went on and the available trace elements were depleted, it couldn't grow the thick dense skeleton that it once had.

The difference was easily distinguishable just to look at it.

Similarly I've seen lots of branching LPS pieces brought in - some are dense and thick, others thin and brittle (same animal). I do think that there are many variables that come into play, but available calcium (and magnesium) and perhaps other trace elements *are* very important to coral growth.

Jenn