[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Lowering pH when adding hard water nutrients to soft water



> Date: Sun, 3 Sep 2000 00:05:53 -0400
> From: William Beckerman

[quoting me]
> >...If you _always_ add the same amount to the gallon of fresh
> water, then its concentrations should remain fairly constant.
>
> OK this may fall under the heading of dumb newbie question
> but... When I kept reef tanks, I always topped off for evaporation
> with R/O water to keep the water chemistry from building up.
> Water changers were away done with reconstituted R/O (R/O
> right, salt etc). Why isn't it this way in fresh water?...

It is.

I trimmed down the portion of my posting that you quoted to the one
statement that I believe caused your confusion.

The gallon of freshwater that I'm referring to here is simply the jug of
water used to mix the "stock solution". When it's empty, refill it with tap
and add the same amount of compounds every time you mix it. Just like making
a marine mix for change-outs.

And we are talking change- outs here, not top- offs. Since she's looking for
stability, she wants to reach the minimal buffering point - around 50 - 80
ppm or so. At these concentrations, even with frequent change- outs, she may
indeed experience a slight build- up over a very long run if her evaporation
rate is excessive enough. But even something as extremely large as, say for
demo only, 25%, you're still only talking less than 100 ppm total. A long
way away from what could occur in a marine tank with its concentrations.

> ...Many of the post seem to indicate that they top with tap
> water or aged mixed water, or is just covered by big water
> changes every week?

Top- offs are _rarely_ mentioned in freshwater conversations. Almost all of
the discussions center around change- outs when it comes to the chemistry...

> ------------------------------

> Date: Sun, 3 Sep 2000 00:09:39 -0500
> From: Paul Krombholz

> ...I would start with the Vancouver water and add small
> amounts of dolomite, which should supply enough calcium.
>  It would be worth her while to get a calcium testing kit so
> that she would know how much calcium is in her tank water...
> I would add only enough dolomite to get the pH to the
> desired value.  That should supply enough calciunm for the
> plants.  A little bit of magnesium sulfate (epsom salts) will
> supply magnesium and sulfur without affecting the pH, and
> some potassium chloride or potassium sulfate will supply
> needed potassium without affecting pH...

Paul -

This is *exactly* the route she was taking and the cause of her frustration.
She was posting in an effort to circumvent this sometimes tedious
procedure - especially in her small tanks  ;-)

> ...If new growth is pale, some form of chelated iron should
> help.  the fish should supply the rest.

Considering the success rate most often reported for the water in her area,
this overlooked factor may play some significant role in her original
problem...

-Y-