[Killietalk] I need some help with water chemistry and additives questions.

[Jason <rusticitas at yahoo_com>]

[I tried posting this 2+ days ago, but it never appeared on the mailing
list, I am posting it again here.]

A recent question I posted on a planted tank forum has re-opened
questions I have about water chemistry, specifically when mixing new
water for water changes. I thought I had started to get a handle on
this, but now I'm not so certain any longer. In general, my questions
form around re-mineralization, carbonates/bicarbonates, pH, hardness
and alkalinity (just to name a few!).

All of this centers around how I have been mixing water change water
for all of my tanks (planted, killies and some livebearer) over the
last year or two. I have been, without any obvious problems, mixing up
a 20 gallon bucket of fairly hard water, then diluting that as
necessary depending upon which tank(s) I am changing the water for. The
mixture I had settled on (about a year ago) is: 20 gallons of city tap
water, 16g Seachem Equilibrium, 12g Seachem Alkaline Buffer, 6g Seachem
Acid Buffer (that is 2:1 ratio for pH7 as per Seachem's instructions).
This resulted in water of approximately 450-500ppm TDS, pH 6.5-7.0, and
alkalinity of ~4-4.5dKH (I forgot to take note of GH reading, but I
think it is between 4-6dH).

I had settled on this mixture as a result of some experiments while
teaching myself about water chemistry for my planted and killie tanks.
My concern at first was, for my planted tanks, that my city's water was
too soft (~40ppm TDS, 0-1dH, 0-1dKH), but thankfully neutral (7pH). So
I started adding some Equilibrium which worked nicely by adding Ca and
Mg for the plants.

Then I was concerned about the acid buffering capacity and the fact
that alkalinity was so low, and that the fish waste would precipitate a
rise in NH3/NH4, drop the pH and generally create a toxic environment.
Then I started to mix in Alkalinity Buffer. This, of course, drove up
the pH. That made me concerned for the soft-water fish (ie. killies),
which seem to want/prefer neutral to acidic pH's. I could not figure
out how does one get some buffering, yet keep a neutral pH. Then I
found Acid Buffer, and after some wrangling and experimentation,
started to use it.

I had these concerns both from readings, and observations (even if
ultimately incorrect). I then just got very used to mixing my source
water in that fashion, and had not questioned it. Until now!

I've never had any problems with the water (per se) with regards to
fish health. However, as mentioned above, a recent question on a
planted tank forum got me a reply saying it's really not a good idea to
use pH altering products in planted tanks. (I am assuming, until I get
a further reply, that they're referring specifically to Acid Buffer, as
I believe Alkaline Buffer is "effectively" baking soda/powder for
bicarbonates).

Now, I would *really* prefer to only have one way to mix the source
water for all water changes, and dilute as necessary for the intended
destination tank.

With regard essential for fish health and breeding, rather than plants
per se, I have the following questions:

(1) Do I even need to worry about alkaline buffering? If so, that will
always raise the pH, correct? And if so, how the heck does one get
alkalinity and a neutral to acid pH? (That doesn't seem possible to
me.)

(2) When talk is of "remineralization" (say for RO/DI water), is it
referring only to GH, and therefore Ca and Mg addition to the water?

(3) Does NaCl come into play with killies at all, beyond some of my
readings recommending it to help prevent/cure ich?

(4) Can "ideal" water parameters be broken down by genus of (killie)
fish? That is, would, say, Aphyosemion and Fundulopanchax use very soft
(<100ppm) water, and Nothobranchius use medium-to-hard water (200+ppm)?
Does one genus like or need NaCl? (I think this one is a big can of
worms, no pun intended.)

(5) Could I possibly make this posting more complicated?

I currently keep: Fp. gardneri Misaje, Fp. cinnamomeus, Ep. roloffi,
Plataplochilus cabindae, A. congicum Z82/17 (fry growing out from
eggs), A. bivittatum Funge (fry growing out from eggs), Procatopus
similis Moliwe, Simpsonichthys reticulatus Xingu (growing out from
eggs), and Terranatos dolichopterus (eggs not yet hatched). There are
some others not yet hatched from eggs yet, notably a couple of Notho
species. For livebearers I have panda guppies, and Limia tridens.

Again, I apologize for the long message here, but I felt the background
might help avoid a long back-and-forth questioning and assist in
getting to the point(s)! And point me in the right direction. I don't
mind doing more reading, research and experimentation. I've just lost
the forest for the trees, so to speak. :-)

{ Jason Stanford - rusticitas at yahoo_com - Bethlehem, PA, USA }


       
____________________________________________________________________________________
Looking for a deal? Find great prices on flights and hotels with Yahoo! FareChase.
http://farechase.yahoo.com/
Join the AKA at http://www.aka.org/aka/modules/content/index.php?id=9.
Archives are at http://fins.actwin.com/killietalk/
Modify your subscription at http://www.actwin.com/mailman/listinfo.cgi/killietalk