Sodium Chloride type salt, without additives is good for use when you have a
nitrite spike, as the chloride ion is preferred over the nitrite ion in
crossing the gills. Nitrites will cause brown blood disease, where the
blood cells go from red to brown, making it impossible for them to transfer
oxygen. Some books say that salt can be used for parasite removal, but it
takes a significant difference in salt content, between the normal level and
the treatment level, so if you have salt in the pond all the time, the level
has to be raised by at least 0.3%.

Potash, which can also be 0,0,60 is a fertilizer and is good for the pond,
as the potash is generally expended, while nitrates and phosphates are
generally available. Algae will grow without the potash, but the higher
level plants need potash. Add about 1 tablespoon per 1000 gallons per
month.

Epsom salt can be used to raise the hardness, by raising the magnesium,
where hardness is defined as the calcium and magnesium content. It has been
used for treating dropsy, as shownb on
http://www.mu.edu/~buxtoni/puregold/home.html

--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html

"Peter Breed" wrote in message
...
Bill Stock wrote:
"robv60" wrote in message
ups.com...

would adding potash (muriate of sulfate magnesia, 0-0-22, epsom
SALTS)have the same benefits for fish as adding pond salt to the water?
Or is epsom salts a different breed of salt all together? How much to
add to a 1200g and 1750g pond for floating plant health?



Muriate of Potash is KCL, Epsom Salts (Magnesium Sulphate) is MgSO4+7H2O.
Both can be good for your plants, but neither has any Sodium (Salt). I
add both of these to the aquarium plants and Potash to the pond. Floating
plants also need Phosphate, but I imagine your pond has lots of Phosphate
already.



I think the point robv is getting at is with regards to osmotic pressure,
and he is right that adding epsom salts (MgSO4) or potassium chloride
(KCl) would have similar osmotic effects as common salt (NaCl - sodium
chloride).
What I am not qualified to comment on is whether this would do the fish
any good, I am no biologist.
On a point of language, as far as a chemist is concerned (and I am one) a
salt is compound in which there is complete charge seperation, eg Na+ Cl-,
it doesn't just refer to common salt. I am just pointing this out as a
potential source of confusion; I am not arguing that nonchemists should
take on board our definitions.
Peter Breed, M.Chem, D.Phil