sophie wrote:
I didn't think the plants actually filtered visible bits out of the
water? (nitrates are about 12.5, which is what they usually are, so
though they haven't gone up they don;t seem to have been used up
either;
I don't measure for any other nutrients) though the kuhlis have
probably
been rootling around a bit less, which would make a difference.
Though
it always surprises me how little gack is in the sand.

Plants don't filter visible bits out of the water, but you'd be
suprised at what sort of changes can make visible bits disappear. I
have theories but none have stood up to repeated testing. I once was
convinced that cucumbers were responsible for the disappearance of
visible bits as every time I fed my pl*co one the water would clear up
noticeable about two days later. I never did figure out what caused
that mystery (I'm fairly confident that it was not in fact the
cucumber).

I was actually thinking more along the lines of the plants using up the
nutrients and thus killing off any free floating algae you may have had
which would make the water clearer. The floating bits being gone is
probably a result of the fish not stirring up as much junk.

While your tank is obviously not nitrate limited at the moment it may
be lacking phosphate or some other nutrient that caused the plants to
stop growing and the algae to disappear. I don't know for sure though.

Can I add "apart from dwarf gouramis?" He looked fairly snippy to me.

Looking snippy and being snippy are very different. Sometimes fish
flare up like that precisely so they don't have to be agressive. He
could be just telling the other fish to stay away because he's in no
mood.


as they're schooling fish I think he might be even more unhappy on
his
own. At the moment I'm going for letting nature take its course.

I thought the same thing, which is why I didn't have a suggestion for
you. Hopefully it will work itself out.

the other tank, on the other hand (coldwater) had no feeding going on
at
all and I came bcak to nitrates of below 12.5, algae all over the
glass
and a mild case of green water. I bloody hate goldfish.

Indeed. Goldfish are second only to lobsters/crayfish in their
destructive power over an otherwise stable aquarium.

-Daniel