Re: NANFA-L-- pH and fin erosion/rot

Scott Davis (
Thu, 25 Aug 2005 10:04:34 -0700 (PDT)

Just a word about using Melafix & Pimafix as tonics.
Anecdotal evidence with softwater killies would
suggest that those plant based items are helpful in
encouraging the healing of torn fins and skin bruises.
However, long term, especially in water with a low
mineral content, they can encourage a pH plunge
resulting in acidosis or "crazy man's disease" -
really the crazy fish disease. If your tap water is
really hard and well buffered, that probably is not
such a big issue. If the water is too high in Ph,
there is a situation called alkalosis, where again the
fish (depending upon the tolerance of the species or
strain) can get really skittich, may swim wildly and
bang into things and can perish. Those situations are
among the reasons why several of the aquarium books
suggest many species will do fine in most waters, "so
long as extremes are avoided."

If you have a ready source of clean rainwater, R.O.
water or demineralized water from the more expensive
processes, you might use it to cut your tap water when
doing water changes. Marching down the water's mineral
content that way should lower TDS and hardness and
probably, as the usual biological processes take
place, should moderate the pH. It is hard to do too
many partial, even daily water changes. After all,
local water tables are doing that for streams all the

Wonder how moderation of surface turbulence, though it
may be-in-the cost of increasing the oxygen content of
the water, would also cut down on the release of
carbon dioxide, which in turn might keep the pH from
rising quite as far.

Seem to recall mention of some plants which will
slightly acidify the water, just as there are some
(Val?) which may do the opposite.

If any of these suppositions are out of line, there
are certainly those on this list who can correct these
guestimates - and please do so. Hope something here is
of use.

All the best,
Scott Davis
non-chemist in the Thorncreek basin

--- Mysteryman <> wrote:

> Lori Austin wrote:
> >I have a few tanks set up with grass pike. In one
> tank a small individual (3.5") appears extremely
> healthy, eats well etc. But, just recently I
> noticed the edge of all fins begining to turn white
> with some appearing ragged. I have read that
> extremes in pH may lead to fin rot...or stress that
> can cause bacterial fin rot. The pH of my tank is
> on the higher side of normal for freshwater-in-8.23.
> Is this higher than normal pH enough to cause
> stress that could lead to fin rot??? What are
> other causes if not and will salt help with the
> cure?
> >
> >
> >
> >
> Why is your pH so high?
> At that level, the ammonia in your tank can be a lot
> more toxic than it
> would be-in-normal pH values, possibly causing at
> least some of your
> problem. Have you tested your ammonia level?
> Salt won't help with that, but it will help with
> nitrite if that's also
> a problem. Otherwise I wouldn't personally bother
> with it unless actual
> bloody finrot was confirmed.
> Melafix & Pimafix are pretty good tonics which can
> help heal and stop
> further damage, but getting your pH down to normal
> and giving the tank a
> good cleaning would probably do a lot more good.
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