Leslie,

One thing that must be considered with your terra cotta pots is country of
origin. If your terra cotta pots are low fired pots from Mexico or Central
or South America, they can have heavy metals in them that could affect your
fish. Lower fired terra cotta has more of a matt finish to it and has a
dull ring when hit with the finger. A high fired terra cotta like you get
from the US or Europe, primarily Italy will have a finish smooth appearance
and when hit with finger will have a slight ring that is almost like doing
the same on a fine piece of lead crystal. Oh, by the way, while you are
hitting your prospect pots with your finger, remember, if you don't get some
kind of ring the pot has a flaw in it and will probably break or crack
prematurely.

By-the-by, you should also be wary of glazed products from these countries
because of a lot of times the glazes have a lot of lead in them.

HTH

Tom L.L.
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"manzara" wrote in message
news
hello,

I have an indoor pond approximetly 5 months old...water chemistry is
perfect. Recently my shubunkins and koi starting acting strange (crowding
together, skiddish). A pond expert reccomended a medication for parasites
and water changes. Both the medicine and water changes worked
wonders...however it is now going on a week and I am beginning to think it
is more the water changes that are helping and not so much the medicine.
Long story short...are clay pots toxic in ponds i.e. could they be
leaching something bad into the water? Perhaps this is why the water
changes help so much?

Thanks,
Leslie