epoxy

[John Gourley]

Hafa Bruce,

I would be interested in hearing why you prefer the portland cement mixture
over an epoxy mix....

I have seen (and used once) the portland cement mixture (the Univ. Guam
special mix) and personally thought it was a bit messy as a turbidity plume
surrounds the coral that is being attached (it forms as the cement mixture
is removed from the plastic bag) and the attachment point was a little
difficult to see. Additionally, hand mixing it underwater in a zip-lock bag
was a little time consuming and the hardening time was longer than epoxy,
so in some cases you had to hold the coral in-place or use a rubber band
(or whatever) to keep it in place long enough for the cement to harden. So,
if you had a lot of coral to attach you could literally spend days under
water ........

I have also used a two-part marine epoxy that had to be mixed in the boat
and then transported to the divers in plastic bags. It had a fairly short
working time so you had people in the boat constantly working the epoxy to
a point where it could be used. Using this operational procedure was very
time consuming and awkward as all the corals basically had to be in place
before the epoxy was sent down to the divers. Timing and coordination was
important and we lost more than one bag of epoxy that hardened on us before
we got a chance to use it. This particular marine epoxy worked well and the
transplanted corals appeared not to be affected at all (from the epoxy)
when checked 6 months later.

The most efficient coral attachment material I have used was a small pistol
grip shaped epoxy gun (with a disposal cartridge) and found it worked
extremely well and allowed one person to attach numerous corals within a
relatively short period of time. The two-part epoxy was mixed together as
it was extruded from the nozzle and there was no plume to restrict
visibility. Additionally, the set time was fairly rapid. However, I do not
remember the brand name.........

Whatever non-toxic attachment material you use, one should consider the
number of corals you have to attach, the physical conditions (currents and
depth) of the site, number of personnel available and whether you have the
time (and $$$) to spend on the project.

Just some thoughts.......

John

********************************
Bruce Carlson wrote:

> We use Z-Spar Splash Zone compound in our aquariums.  It's available at
> marine supply stores.  However, I would recommend using portland cement
> mixed with plaster-of-paris (about 10:1 ratio) rather than epoxy for
> planting corals in the ocean.
>
> Bruce

> *******************************
> At 02:38 PM 2/6/2001 +0000, N.D.Chapman at hw.ac.uk wrote:
> >Hello,
> >I was wondering if anyone knew of any brand names (and company if
> >possible)for epoxy resin used for underwater fixing of corals to hard
> >substrate.I have seen it being discused in e-mails and mentioned in
> >papers and could use it for a similar application.
> >Thanks
> >Nikki




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