Biorock accretion experiment thread


My personal opinion on the matter would be ‘a material that provides improved conductivity and/or mineral growth’ rather than necessarily more strength. Given the lower voltages and long times required for aragonite production, strength shouldn’t be a major factor. However, finding materials that could either improve the flexibility, energy efficiency, or growth rate of the accreted material could be a huge boon.


I figured it would be enough to keep burrowing pests out of the paint, and oxygen off the steel.

(.) #32

There are several indications to that at extensive depts the physical and may be
chemical characteristics of seawater is different due to high pressure.

There is also some indications to that, this characteristic change is in favor
to the accretion process.

(.) #33

There was an experiment where the accretion process was measured at different
depts, and they found no difference of accretion.
I think they forgot to calculate with electric power loss due to the lenght of the wire.


Been a while since I replied here: Looking for a 3+ amp 1.5V stepdown power supply and alternate electrodes before experimenting any further. It will be interesting to see if there is a marked reduction in erosion and what sort of accretion takes place with a proper power supply.

(.) #35

I was contemplating on the same thing. A conversion of voltage to 1.5V.
The simplest thing I can come up with is a solar panel 12V dc and a power
converting, commercial unit to 120V ac, and then down convert to 1.5 ac
and a diode to make it dc, or diode bridge, or zenner bridge with capacitors.

The most elegant would be is a solar panel with 1.5V dc output and a voltage
regulator ot 1.5V

Other possibility is to get one of those single unit solar panels that have a 120 ac
converter built in, and down convert to 1.5 and make it dc.

Other power sources could be used too, like a wind generator, a diesel generator,
an under water propeller with a generator in a current.

(.) #36

I tried to get graphite electrodes from a D battery.
There is graphite in the battery, but it is in very fragile state.

During my childhood, in Esat-Europe, there were 4.5V batteries by linking
3 1.5V battery pieces in series. Each battery unit had a graphite rod in the middle.
Those were about 1/4 inch diameter and 3 inches long graphite rods.
Those were solid.

The next step I plan for graphite rods is pencils.
May be the carpenter pencils from Home Depot.
Home Depoting the seastead.

(.) #37

I am also planning to look around in welding supplies at ace hardware and
harbor freight tools.

(.) #38

I would just like to mention in connection of a medical seastead,
the human body accretes bones. If electrodes accrete calcium and
magnesium carbonate and sulphate from seawater, similar small electrodes
could accrete bones

May be osteoporosis treatment? Zap them!


Graphite rods you might want to hit Amazon (They have some listed as explicitly intended for eletrical experimentation) or a specialist local store. I’ve tried with a variety of pencil lead rods (but not a battery electrode) and all of them failed within a few days/weeks. Raising the voltage above 2-3 volts sees them de-laminate within a day or two, below that (I didn’t check voltage on my early attempts, where the same lead lasted much longer) they will last a week or two but begin slowly dissolving or develop stress fractures and begin peeling apart.

(.) #40

Some articles, may be Hilbertz, talk about lead electrodes.
I wonder if those get used up. May be not.

(.) #41

It is probably possible to build a conversion unit that does a 12V dc aconversion to 12V ac,
and transform 12V ac to 1.5V ac and then the 1.5V ac to 1.5V dc.

(.) #42

And still the 1.5V dc potential may not be enough to pull 3 amps across the electrode.
May be multiple electrodes with a manifold and paralell connection for the electrodes
might be able to pull higher current.

Though it is not the current that produces the precipitation, but the pH change
due to the electrolysis.

I guess. I should build.


Given that modern computers have a lot of 3.3v parts in them, and large computer psu are rated 20amps or more at 3.3vdc, and your power distribution system will likely loose a volt from the psu to the underwater electrodes, making 2.3v become whatever you want below that becomes trivial. So is adjusting the psu to output less than 3.3v.

But the stupidly cheap way, and most versatile way, is to pay $0.80 for this 3amp adjustable regulator, and use one at each electrode location. You can feed it 12vdc from a car battery, or up to 20v off a “12v” solar panel, or off a laptop deskwart psu.

Or am i not understanding the problem again?

(.) #44

You got it! I will accrete you a cinderblock.


How will you get the cinders into the accreted material? Coal and wood cinders are non-conductive.

(.) #46

Hilbertz already solved that problem. He used sand and seawater between the electrodes.
I’ll just borg it.


Ok, why will you use cinders?

(.) #48

Not cinder, just cinder block. For the size and shape definition.
Instead of rectangular shaped concrete masonry unit.

I am not interested about cinder. Though roman concrete used volcanic ashes.
Roman concrete lasted for 2000 years and still ticking.

May be , there is something in cinder.


What if the hull of the desired structure is built relatively cheaply out of marine plywood, than turned up side down and the bottom and half of the freeboard is covered with several layers of galvanized mesh stapled to the plywood. .

Than, the structure is floated ballasted to a waterline level equal to the end of the mesh layer on the freeboard, and run the biorock experiment through the mesh. Would that layered mesh speed up the accretion process or make any difference? Just wondering,…

The idea would be to have a functional structure in which the biorock accretion is NOT used for initial building purpose, but rather to further strengthen the hull and MAINLY to lower its maintenance cost.