[ScubaSteve]

Awesome! This is what I like to see! Ok, Let me respond to each of these in turn...

Originally Posted by Kryptic4L

would this not be equivelent to a farmer's feild where as the lime becomes the ideal soil.

Still not sure how this translate's to us, as the plating draws in mineral's thus creating more farming land. Which would be something we have more control over on the smaller scale .

Also, my train of thought would lead toward's if they are placed in a tank, and the plating is drawing more of the mineral's near the electrically charged area. This could potentially take nutrients away from subject B putting it at a disadvantage where A gains a slight advantage.

Krytic4L, let me first say, no one really knows how or why this works so I don't really have a definitive answer. I was thinking along the same lines as you so I went looking for previous research results and found a few things that might answer that thought.

First, the minerals that deposit are nearly the same as the limestone substrates that coral usually grow off of, so this might not explain accelerated growth. Second, when testing this in the Maldives there was a major bleaching event (heat) that wiped out most of the natural reefs and damaged the Biorock reefs; what they noticed was that areas of the coral that were closest to the cathode structure were unscathed (ie. bottom and sides) and the parts furthest away bleached. The natural reef next the the biorock saw the corals bleach all over. Third, when they shut off the power for a period of time the coral growth appeared to slow. From this, it suggests that the charged electrode is playing some active role though no one knows what; it could be as you suggest where it's sort of like a fertilizer... but I hypothesize it's not the additional growing "land" that makes the difference.

Also, our tanks and the oceans have far too much flow to create regions of feast or famine. Ok, if you ran with no pumps, yeah that'd be the case but who does that? If there is a region of high dissolved mineral concentration it'll only be at most a millimeter thick around the rack.Yes, the structure itself does pull calc, alk and mag out of the water (thus needing to dose) but at a rate not much faster than a large mother colony would (I do have some data on accretion layer growth rates).

Originally Posted by vic622

With respect to the metals leaching, and not getting technical, could there be a way to create a grid using carbon fibre/rod/mat rather than metal?
I'm not sure about the potentials, or if there is an anode/cathode issue, but it might solve the problem of leaching once the current has been turned off, enabling the base material to be retained and have SPS growth directly on the base?!?

Vic, that is a concern of mine as well. The corals would likely be easy to remove from the structure so you wouldn't need to worry much about metal left behind. In addition, the cathode structure is protected from corrosion while the device is in operation. The anode is more of a concern and will likely be carbon, titanium or magnesium.

But to answer your question, yes you can make the mat from carbon. This is something I'm considering but it might be an expensive option (it'd be nice if I could grow it onto charcoal/activated carbon ). What I would like it to have is a frag plug that you basically plug in and you do all your growing on that and not have to worry about the rack.

Originally Posted by banditpowdercoat

The way I see it, if the limestone builds on the structure first, then Corals grow on limestone. You just chip off limestone/coral and voila, a frag to relocate. Or, just take clippings off, utilizing the 3-6x growth rate. A little structure in the corner of ones tank could be used to propagate frags continously. No need to worry about turning the electricity off, leeching etc. just keep growing. Also, for frag businesses, this could mean a great help. Set up complete tanks with mesh growing surfaces in them.

You're spot on!