Richard, I have 14 of the Kasco and Ice eater brand deicers going
currently. The do need water depth to be effective and do not work well in
shallow water, but there are some things you can do. They work best when
driving the warmer bottom water up a slope to shallower water. If you can
get the deicer in deeper water off the dock facing towards it you will do
much better. You can do this with a couple of polyballs and some cinder
blocks. The deicers have additional holes in the sides to make it hang at
an angle to direct the water flow. The Kasco models use the cage for offset
hanging. Place the unit off the dock in deeper water facing towards shore.
The units can be placed very close to the bottom, almost touching. The
units have to be checked often for debris caught in the blades, they will
suck up any rope or plastic anywhere around. The trick in future years is
to have everything setup before the ice hits, but it certainly adds to the
fun to try it on ice covered decks and pilings. FWIW, I would return the
1/2 hp model and get the 3/4 HP. Much better coverage with just a few more
amps.

"richard" wrote in message
oups.com...
update- I get the 1/2 HP deicer at WM and go to RI where the dock is.
the river is frozen at the pilings already. (and the dock is suspended
in the air for the winter.) as planned we arrive at high tide so we are
as close to the ice as possible. we chop the ice with all sorts of
things not designed for this job. the pilings have actually already
been moved sideways a few inches by the ice. we chop a hole big enough
for the deicer at the deepest end of the dock and hang it with the two
lines that are supplied. Turn it on and wow it works, but I am
concerned about the water at low tide. so after visiting the sisters
and brother we come back at low tide to find that it is very shallow
indeed. At the deep end, with the deicer about 6 inches from the
bottom, the top of the deicer is almost touching the surface of the
water and it turns out that this is not a particulary low tide.
Not sure what to do at this point, afraid that there is just not enough
water and since it is very cold, I think that it might be too late in
the season for something clever like building a mount that puts the
deicer in deeper water.
Oh well, any ideas?