We are working on a seastead design that will have a 40 by 16 foot living area above the water.
There will be 4 foot wide columns that are about 20 feet long going out from 
from the 4 corners of living area and down into the water at 45 degrees, which half of
each column under water.   The bottoms of the floats will make a rectangle about 44 feet wide and 68 long.
From the bottom of each column there will be 
2 cables going to the adjacent corners to hold it in place.
There will also be a cable making a rectangle between the bottoms of all the floats so we have some
redundancy in case one cable breaks.
The seastead is about 30,000 lbs I think but this is NOT a normal boat hull shape,
it is more like a tiny oil platform as far as drag.

We expect to use 2.5 meter diameter propellers on two submersible mixers and solar power to move
at around 1 MPH plus any help from using eddies.

Because of the cables, dropping an anchor from the living area would be trouble.  I am hoping we
can have a rope/chain go under a leg/float and have the anchor below the end of the leg when not 
in use and lower from there when in use.   Should this plan work?   

If the leg/float is duplex stainless steel it might avoid galvanic corrosion issues if the anchor
and chain were also duplex stainless steel.  Can we get chain and anchors in duplex stianless steel?