Re: NANFA-- RE: diseased sunfish

unclescott (
Tue, 22 Apr 2003 10:37:38 -0500

> I usually change 100 % in breeding tanks or species tanks (mostly killis)
every week. With young fishes I do this 2 to 7 times a week depending on
species and size. My philosophie is that fish are the healthier the more
frequent water changes they get (with some limited exceptions for highly
specialized fish from not-running biotopes).

Hello Steffen!

When I hear of someone making 100% water changes my thoughts range from
admiration to jealousy to a little bit of apprehension. The first two
emotions are my problem, but I've a question pertaining to the third.

In the tanks in which you change 100% of the water, do you have filtration
and/ or gravel and plants which would hold most of the beneficial bacteria?
I recall reading somewhere that most such bacteria actually does not reside
in the water, but on tank sides and presumably upon any other physical
structure. On the other hand, there was a fish care book written some time
back which warned that large water changes (presumably in bare tanks) might
actually reverse the nitrogen cycle.

I would assume that frequent massive changes from the same water supply
would not allow the water's chemistry to change so significantly as to shock
the tank's residents. I've just never had the nerve and the time/ resources
to maintain such a regimen.

By the way, a number of killinuts were dismayed some time back to discover
that your killie book issued by Barron's was no longer being printed. It was
terrifically handy to pack an extra copy or two and when a person new to
killies would repeat the magic question, "Do you know where I could get a
good introduction to killies?" to pop a copy of "Killifish; A Complete Pet
Owner's Manual" out of a brief case or fish box and present it to them. :)

All the best!

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