Where to test the water

[Roger Mellie]

I have had a few problems with my goldfish since getting them which all seem
to be caused by water quality issues. They currently seem to be exhibiting
all the symptoms of acidosis/alkalosis (see
http://users.megapathdsl.net/~solo/puregold/disease/symptom/byname.htm#ACIDOSIS).

However when I test my tank water it always seems to be fine - except for
when I first started and had problems with nitrites and nitrates.

What I wondered is if it matters WHERE in the tank I get the test samples.
So for example if I always fill the tube directly in front of the outflow of
the filter, the water may always appear fine, but if I dig down to the
bottom of the tank in a corner (not sure how) it may be poorer quality.

Or does it not matter?

[Geezer From The Freezer]

Roger,

Shouldn't really matter. The filter will push the water around so
it should mix all over. IF your worried take a sample from the mid section
of the tank.