Soft Water Anyone?

[Joe Crowder]

I need a sanity check from the experts.

I have a 10 gallon tank with about 7 adult Endler's Livebearers, and over a
dozen fry, no substrate, a big mass of java moss, and some duck weed. It
has been set up since April, but has never really flourished. I've had some
casualties, mostly among the males, and I've noticed a definite tendency
toward female Fry. I'm pretty sure that inbreeding is not an issue because
I got the males from one source, and the females from another source in a
different part of the country. I've also noticed that snails do not survive
in this tank. Up until recently, I assumed that was due to a lack of food
since there is very little algae in the tank.

Now having said all that, here are my water parameters as of last night just
before I did a water change: Ammonia - 0 ppm, Nitrate - 15 ppm, pH - <6
(bottom of my scale), GH - 3 dGH. Anyone see the problem yet? I'll give
you another hint. I got a test kit for KH today, and guess what the KH was
less than 1 dKH. I also tested the tap water this evening: pH - 7.8, GH - 3
dGH, KH - 3 dGH.

So, here is my conclusion: Something (plants, snails, ???) is using up what
little alkalinity I have in my very soft water to begin with, and my pH is
crashing. I haven't seen this in my other tank because I have flourite as a
substrate which is probably acting as a buffer.

Based on my reading, and the advice from the LFS (he actually said to skip
the KH test), the corrective action is to add CaCO3 in the form of aragonite
(crushed coral), limestone, marble, etc. The CaCO3 which will bring up the
KH, GH, and pH to a more reasonable level. Adding Baking Soda, would raise
KH and pH, but not affect GH. I've added a cupful of aragonite to my tank a
start. Now, I think I am in for some experimenting. I need to figure out
how much aragonite to use, and how often to replace it. I've started with a
cupful just thrown on the bottom. I did not wash it because I want the dust
to dissolve a little quicker to get the whole process started.

Now for my questions:
1) Are my conclusions correct?
2) Is the corrective action I've described correct? Is there a better
material/process to add CaCO3?
3) Is there any reason to also use baking soda (NaHCO3)?
4) Any suggestion on amount of aragonite to use?
5) Any suggestions on replacement schedule? How long will it last before
depleting? weeks? months? years?
6) Could this be some sort of seasonal thing from the city water supply?
7) Should I worry about my other tank? Will the buffering from the flourite
eventually run out?

Any advice or comments would be appreciated. I'd especially like to here if
anyone else has tried this in their own tanks.

TIA
Joe

p.s. Anyone want to trade some of their hard water for my soft water? Maybe
I should start looking at discus or some other soft water fish.

[Charles]

On Mon, 19 Jul 2004 22:57:03 -0400, "Joe Crowder"
> wrote:

>I need a sanity check from the experts.
>
>I have a 10 gallon tank with about 7 adult Endler's Livebearers, and over a
>dozen fry, no substrate, a big mass of java moss, and some duck weed. It
>has been set up since April, but has never really flourished. I've had some
>casualties, mostly among the males, and I've noticed a definite tendency
>toward female Fry. I'm pretty sure that inbreeding is not an issue because
>I got the males from one source, and the females from another source in a
>different part of the country. I've also noticed that snails do not survive
>in this tank. Up until recently, I assumed that was due to a lack of food
>since there is very little algae in the tank.
>
>Now having said all that, here are my water parameters as of last night just
>before I did a water change: Ammonia - 0 ppm, Nitrate - 15 ppm, pH - <6
>(bottom of my scale), GH - 3 dGH. Anyone see the problem yet? I'll give
>you another hint. I got a test kit for KH today, and guess what the KH was
>less than 1 dKH. I also tested the tap water this evening: pH - 7.8, GH - 3
>dGH, KH - 3 dGH.
>
>So, here is my conclusion: Something (plants, snails, ???) is using up what
>little alkalinity I have in my very soft water to begin with, and my pH is
>crashing. I haven't seen this in my other tank because I have flourite as a
>substrate which is probably acting as a buffer.
>
>Based on my reading, and the advice from the LFS (he actually said to skip
>the KH test), the corrective action is to add CaCO3 in the form of aragonite
>(crushed coral), limestone, marble, etc. The CaCO3 which will bring up the
>KH, GH, and pH to a more reasonable level. Adding Baking Soda, would raise
>KH and pH, but not affect GH. I've added a cupful of aragonite to my tank a
>start. Now, I think I am in for some experimenting. I need to figure out
>how much aragonite to use, and how often to replace it. I've started with a
>cupful just thrown on the bottom. I did not wash it because I want the dust
>to dissolve a little quicker to get the whole process started.
>
>Now for my questions:
>1) Are my conclusions correct?
I think they are.

>2) Is the corrective action I've described correct? Is there a better
>material/process to add CaCO3?
maybe dolomite, adds magnesium as well as calcium, or add some epsom
salts.

>3) Is there any reason to also use baking soda (NaHCO3)?
It's quicker for a pH emergency. I don't think you are there yet.

>4) Any suggestion on amount of aragonite to use?
some. It will dissolve as the water will take it, more will not
dissolve.

>5) Any suggestions on replacement schedule? How long will it last before
>depleting? weeks? months? years?
Test the water from time to time. I would guess it should be good for
a year.

>6) Could this be some sort of seasonal thing from the city water supply?
Best to ask them.

>7) Should I worry about my other tank? Will the buffering from the flourite
>eventually run out?
Probably. Test the water from time to time.

>
>Any advice or comments would be appreciated. I'd especially like to here if
>anyone else has tried this in their own tanks.

My water runs 55 DH from the tap, I don't need to add anything, except
more water would be good.

>
>TIA
>Joe
>
>p.s. Anyone want to trade some of their hard water for my soft water? Maybe
>I should start looking at discus or some other soft water fish.
>

--

- Charles
-
-does not play well with others

[Cris]

On Mon, 19 Jul 2004 22:57:03 -0400, "Joe Crowder"
> wrote:

>I need a sanity check from the experts.
>
>I have a 10 gallon tank with about 7 adult Endler's Livebearers, and over a
>dozen fry, no substrate, a big mass of java moss, and some duck weed. It
>has been set up since April, but has never really flourished. I've had some
>casualties, mostly among the males, and I've noticed a definite tendency
>toward female Fry. I'm pretty sure that inbreeding is not an issue because
>I got the males from one source, and the females from another source in a
>different part of the country. I've also noticed that snails do not survive
>in this tank. Up until recently, I assumed that was due to a lack of food
>since there is very little algae in the tank.

Snails need calcium - your tap has very little. You'll may notice
some pitting, weaknesses or miscoloration in some shells (esp. older
snails) if they are calcium deprived.

>
>Now having said all that, here are my water parameters as of last night just
>before I did a water change: Ammonia - 0 ppm, Nitrate - 15 ppm, pH - <6
>(bottom of my scale), GH - 3 dGH. Anyone see the problem yet? I'll give
>you another hint. I got a test kit for KH today, and guess what the KH was
>less than 1 dKH. I also tested the tap water this evening: pH - 7.8, GH - 3
>dGH, KH - 3 dGH.

Sounds just like my guppy tank! Do your water changes more often - at
least 30%, 2x/week as long as your fish load is so high. That'll help
replace minerals and lower nitrate, stabilizing the water.

>
>So, here is my conclusion: Something (plants, snails, ???) is using up what
>little alkalinity I have in my very soft water to begin with, and my pH is
>crashing. I haven't seen this in my other tank because I have flourite as a
>substrate which is probably acting as a buffer.

Flourite is inert, it doesn't buffer at all. The plants and snails
both use up the hardness in the water. Fish waste, leftover food and
rotting plant leaves contribute to the acidity of the water - another
reason for more water changes.

>
>Based on my reading, and the advice from the LFS (he actually said to skip
>the KH test), the corrective action is to add CaCO3 in the form of aragonite
>(crushed coral), limestone, marble, etc. The CaCO3 which will bring up the
>KH, GH, and pH to a more reasonable level. Adding Baking Soda, would raise
>KH and pH, but not affect GH. I've added a cupful of aragonite to my tank a
>start. Now, I think I am in for some experimenting. I need to figure out
>how much aragonite to use, and how often to replace it. I've started with a
>cupful just thrown on the bottom. I did not wash it because I want the dust
>to dissolve a little quicker to get the whole process started.

Aragonite will help a lot with buffering the water hardness. I'm sure
a cup is plenty and will last a very long time - years. I'm using
just 1 or 2 handfulls in my 10 gallon. It's pretty easy to raise
hardness and pH - not so easy to lower them. If you ever decide to
keep soft water fishes you'll be in luck with your water supply! :D


>Now for my questions:
>1) Are my conclusions correct?
>2) Is the corrective action I've described correct? Is there a better
>material/process to add CaCO3?
>3) Is there any reason to also use baking soda (NaHCO3)?
>4) Any suggestion on amount of aragonite to use?
>5) Any suggestions on replacement schedule? How long will it last before
>depleting? weeks? months? years?
>6) Could this be some sort of seasonal thing from the city water supply?

Your water supply may change not only seasonally, but with every good
rainfall or draught.

>7) Should I worry about my other tank? Will the buffering from the flourite
>eventually run out?

If you have a heavy fish load, yes, you should keep an eye on it and
adjust your water change schedule accordingly. You didn't mention
what livestock you have in the other tank. Some fish will do great in
low pH, some not - none will like big pH swings, though.

>Any advice or comments would be appreciated. I'd especially like to here if
>anyone else has tried this in their own tanks.
>
>TIA
>Joe
>
>p.s. Anyone want to trade some of their hard water for my soft water? Maybe
>I should start looking at discus or some other soft water fish.
>

[Mean_Chlorine]

"Joe Crowder" > wrote in message >...


> Now for my questions:
> 1) Are my conclusions correct?

Absolutely flawless.

> 2) Is the corrective action I've described correct? Is there a better
> material/process to add CaCO3?

Any calcium carbonate material will do, e.g. you can decorate with
limestone, or place shells in the aquarium, or... As the
rocks/shells/whatever dissolve, they'll add free calcium and
bicarbonate to your aquarium, raising both GH and KH.

> 3) Is there any reason to also use baking soda (NaHCO3)?

Not really. The calcium carbonate will, fairly slowly, bring your pH
up to about 7.5-7.7 and "lock" it there, which is fine for guppies.
Bicarbonate works instantly, and can also raise pH higher than
limestone, up to 8.3, but neither is really something you need.

> 4) Any suggestion on amount of aragonite to use?

It is not possible to overdose limestone. All that happens if you use
a lot is that it'll raise the pH to 7.5 quicker.
Oh yeah, in case someone suggests blackboard chalk: DON'T. It used to
be limestone (chalk) but nowadays it's gypsum, and while it'll raise
your GH quickly and a lot, it wont raise your KH or buffer your pH.
Oh yeah 2; marble dissolves too slowly to be of much use.
Stay with "real" limestone, chalk, snail/mussel shells, eggshells,
cuttlefish bone, coral, oolite... Crushed/powdered for maximum &
fastest effect, in larger chunks for slower & longer effect.

> 5) Any suggestions on replacement schedule? How long will it last before
> depleting? weeks? months? years?

Depends on amount and structure, as well as biological load in your
aquarium. A very solid limestone rock will last a lot longer than,
say, calcium carbonate powder. Anyway, you're probably looking at a
replacement schedule on the order of months or years, not days or
weeks.

> 6) Could this be some sort of seasonal thing from the city water supply?

Soft water? Probably not. If possible, many waterworks adjust the
water so it is soft (to avoid boiler stone in the warm water pipes)
with a pH above 8 (to avoid corrosion). Sounds like your city water
might be of that type.

> 7) Should I worry about my other tank? Will the buffering from the flourite
> eventually run out?

?Buffering from fluorite?
That will raise your GH but AFAIK wont buffer your pH. It may however
contain some amount of calcium carbonate, which does that.

> Any advice or comments would be appreciated. I'd especially like to here if
> anyone else has tried this in their own tanks.

Just plunk a couple of limestone rocks and/or a bag of coral sand in
the filter and/or a couple of seashells in the tank, and your water
will straighten itself out in a few days to 2 weeks (depending on how
much you plunk in and in what form).

> p.s. Anyone want to trade some of their hard water for my soft water? Maybe
> I should start looking at discus or some other soft water fish.

If you wish, but it's much easier to make soft water hard than to make
hard water soft...

[NetMax]

"Joe Crowder" > wrote in message
...
> I need a sanity check from the experts.

<big snip>

You've already received the expert advice, so here is just an addendum.
I have similar water in the shop, and low pH can be pervasive under your
natural kH conditions, plus you need to overcome whatever is naturally
dropping the kH further in your tank. I've had many clients who have
found this combination frustrating to correct. An option is to siphon
your gravel out (about 5' of 2" diameter hose into pails). This
essentially removes the main acidifying vector, allowing you to correct
the water in a more controlled manner using water changes and/or baking
soda. You can replace the gravel with crushed coral substrate. This
removes the complexity of using your filter system (or hanging bags), and
the greater surface area it provides is more effective than larger chunks
of similar minerals. The coral substrate has otherwise very similar
characteristics to your gravel. It is slightly lighter (in weight), may
increase the brightness (reflection), seems to provide a better
environment for cynobacteria and will still grow plants (though probably
not better than inert gravel).

Another option (I'm currently experimenting with) is a reduced amount of
gravel, sloped, with coral chunks (the size of your pinkie) on top of the
back half of the tank, sloping even higher. This gives me normal
substrate to gravel vac along the front, the effect of the coral and lots
of hiding spaces for fry ;~)
--
www.NetMax.tk

[Cris]

On Tue, 20 Jul 2004 09:47:48 -0400, "NetMax"
> wrote:

>An option is to siphon
>your gravel out (about 5' of 2" diameter hose into pails). This
>essentially removes the main acidifying vector,

How is Flourite and "acidifying vector"? Or inert gravel, for that
matter?

>allowing you to correct
>the water in a more controlled manner using water changes and/or baking
>soda. You can replace the gravel with crushed coral substrate. This
>removes the complexity of using your filter system (or hanging bags), and
>the greater surface area it provides is more effective than larger chunks
>of similar minerals.

I would definitely not replace a Flourite substrate with Aragonite!
Not only is Flourite much better for the plants, but it looks more
natural. Some fish will be a bit freaked out by a bright white
substrate.

>The coral substrate has otherwise very similar
>characteristics to your gravel. It is slightly lighter (in weight), may
>increase the brightness (reflection), seems to and will still grow plants (though probably
>not better than inert gravel).

I don't think he will want to "provide a better environment for
cynobacteria" aka blue green algae.

[NetMax]

"Cris" > wrote in message
...
> On Tue, 20 Jul 2004 09:47:48 -0400, "NetMax"
> > wrote:
>
> >An option is to siphon
> >your gravel out (about 5' of 2" diameter hose into pails). This
> >essentially removes the main acidifying vector,
>
> How is Flourite and "acidifying vector"? Or inert gravel, for that
> matter?

Fourite is advertised as inert, and gravel usually is, and when it isn't,
the effect is to harden the water, not acidify it. The primary
acidifying vector comes from any organic matter decomposing. This
includes feces, uneaten food, dead plant matter etc.

> >allowing you to correct
> >the water in a more controlled manner using water changes and/or
baking
> >soda. You can replace the gravel with crushed coral substrate. This
> >removes the complexity of using your filter system (or hanging bags),
and
> >the greater surface area it provides is more effective than larger
chunks
> >of similar minerals.
>
> I would definitely not replace a Flourite substrate with Aragonite!
> Not only is Flourite much better for the plants, but it looks more
> natural. Some fish will be a bit freaked out by a bright white
> substrate.

At home, I have plants growing in dolomite substrate and in flourite.
Going by my limited experience, they both behave similarly enough to
provide anchor for my plants, trap nutrients and provide water flow. The
nuances between specialty substrates will often get lost on the average
hobbyist with reasonable expectations. The lighter colour freaks some
people as well as fish (not sure which is greater affected ;~).

At work, besides the crushed coral tanks, I use inert gravel of varying
colours and diameters. The plant growth is stunning, photographers are
no longer uncommon and local plant enthusiasts are livid with envy (my
staff gets most of the credit for all the pruning, shaping and planning
done). No flourite or laterite is used, most tanks have no CO2 and my
1.2wpg comes from bulbs which will be 2 years old in 4 months. I can
only attribute the spectacular growth to the higher fish loads I run. I
would suggest to you that flourite's advantage is a fraction compared to
CO2 or in my case, lots of ammonia, and if all other conditions were
bountiful, the flourite would be minimized to irrelevance. I realize
that might run counter to the Internet doctrine of the day, but I call em
as I see em ;~).

> >The coral substrate has otherwise very similar
> >characteristics to your gravel. It is slightly lighter (in weight),
may
> >increase the brightness (reflection), seems to and will still grow
plants (though probably
> >not better than inert gravel).
>
> I don't think he will want to "provide a better environment for
> cynobacteria" aka blue green algae.

I can't presume to speak for someone else's opinion, but I don't think
any of us want cyno, which is why I pointed it out. I have no scientific
evidence for this. At work, I currently have 18 tanks on crushed coral,
and have had cyno on 2 or 3. I have about 90 tanks on other substrates
and one incident of cyno (and not on the substrate). Over the years at
home, I've found my dolomite substrate to be slightly more susceptible to
cyno than natural substrates. Whether this is my imagination, or it was
the lighter colour, or the specifics typical of my hard-water tanks (ie:
hard-water, less plants, lots of carnivores producing waste), I can't
say. It's only observations and my best attempt to recall any relevant
circumstances. jmmv ;~)
--
www.NetMax.tk

[Cris]

On Tue, 20 Jul 2004 19:55:41 -0400, "NetMax"
> wrote:

>I can't presume to speak for someone else's opinion, but I don't think
>any of us want cyno, which is why I pointed it out. I have no scientific
>evidence for this. At work, I currently have 18 tanks on crushed coral,
>and have had cyno on 2 or 3. I have about 90 tanks on other substrates
>and one incident of cyno (and not on the substrate). Over the years at
>home, I've found my dolomite substrate to be slightly more susceptible to
>cyno than natural substrates. Whether this is my imagination, or it was
>the lighter colour, or the specifics typical of my hard-water tanks (ie:
>hard-water, less plants, lots of carnivores producing waste), I can't
>say. It's only observations and my best attempt to recall any relevant
>circumstances. jmmv ;~)

I'm no expert on algae, either, but I have a suggestion that you might
look into. An experienced fish club friend says that cynobacteria
especially flourishes in areas that are low flow or stagnant - I
presume that means low oxygen as well.

[Graham Ramsay]

"Joe Crowder" wrote
> Any advice or comments would be appreciated. I'd especially like to here if
> anyone else has tried this in their own tanks.

Your water parameters are identical to mine and I
kept Endlers without any problems also in tanks
without substrate. Like you I am unable to keep snails
healthy for very long.
I still have some Xiphophorus and Chracodon
species which prefer harder water supposedly
but they do okay in mine.
I have a CO2 injected planted tank and even there
the pH doesn't get below 6.
I find that weekly water changes of around a third
keeps the water sweet. No need to add any minerals
or chemicals.

> p.s. Anyone want to trade some of their hard water for my soft water? Maybe
> I should start looking at discus or some other soft water fish.

Breed Apistos, many Apisto breeders would kill for
water like ours.

--
Graham Ramsay
Learn about the work of the JREF
www.randi.org

[NetMax]

"Cris" > wrote in message
...
> On Tue, 20 Jul 2004 19:55:41 -0400, "NetMax"
> > wrote:
>
> >I can't presume to speak for someone else's opinion, but I don't think
> >any of us want cyno, which is why I pointed it out. I have no
scientific
> >evidence for this. At work, I currently have 18 tanks on crushed
coral,
> >and have had cyno on 2 or 3. I have about 90 tanks on other
substrates
> >and one incident of cyno (and not on the substrate). Over the years
at
> >home, I've found my dolomite substrate to be slightly more susceptible
to
> >cyno than natural substrates. Whether this is my imagination, or it
was
> >the lighter colour, or the specifics typical of my hard-water tanks
(ie:
> >hard-water, less plants, lots of carnivores producing waste), I can't
> >say. It's only observations and my best attempt to recall any
relevant
> >circumstances. jmmv ;~)
>
> I'm no expert on algae, either, but I have a suggestion that you might
> look into. An experienced fish club friend says that cynobacteria
> especially flourishes in areas that are low flow or stagnant - I
> presume that means low oxygen as well.


Agreed. On my web site, I list 'directed water flow' as a possible cure.
Erythromycin is another method, though I generally avoid chemical
solutions while non-chemical methods exist to be tried.
--
www.NetMax.tk

[Joe Crowder]

"Mean_Chlorine" > wrote in message
om...
> "Joe Crowder" > wrote in message
>...
>
>
> > Now for my questions:
> > 1) Are my conclusions correct?
>
> Absolutely flawless.
>
> > 2) Is the corrective action I've described correct? Is there a better
> > material/process to add CaCO3?
>
> Any calcium carbonate material will do, e.g. you can decorate with
> limestone, or place shells in the aquarium, or... As the
> rocks/shells/whatever dissolve, they'll add free calcium and
> bicarbonate to your aquarium, raising both GH and KH.
>
> > 3) Is there any reason to also use baking soda (NaHCO3)?
>
> Not really. The calcium carbonate will, fairly slowly, bring your pH
> up to about 7.5-7.7 and "lock" it there, which is fine for guppies.
> Bicarbonate works instantly, and can also raise pH higher than
> limestone, up to 8.3, but neither is really something you need.
>
> > 4) Any suggestion on amount of aragonite to use?
>
> It is not possible to overdose limestone. All that happens if you use
> a lot is that it'll raise the pH to 7.5 quicker.
> Oh yeah, in case someone suggests blackboard chalk: DON'T. It used to
> be limestone (chalk) but nowadays it's gypsum, and while it'll raise
> your GH quickly and a lot, it wont raise your KH or buffer your pH.
> Oh yeah 2; marble dissolves too slowly to be of much use.
> Stay with "real" limestone, chalk, snail/mussel shells, eggshells,
> cuttlefish bone, coral, oolite... Crushed/powdered for maximum &
> fastest effect, in larger chunks for slower & longer effect.
>
> > 5) Any suggestions on replacement schedule? How long will it last
before
> > depleting? weeks? months? years?
>
> Depends on amount and structure, as well as biological load in your
> aquarium. A very solid limestone rock will last a lot longer than,
> say, calcium carbonate powder. Anyway, you're probably looking at a
> replacement schedule on the order of months or years, not days or
> weeks.
>
> > 6) Could this be some sort of seasonal thing from the city water supply?
>
> Soft water? Probably not. If possible, many waterworks adjust the
> water so it is soft (to avoid boiler stone in the warm water pipes)
> with a pH above 8 (to avoid corrosion). Sounds like your city water
> might be of that type.
>
> > 7) Should I worry about my other tank? Will the buffering from the
flourite
> > eventually run out?
>
> ?Buffering from fluorite?
> That will raise your GH but AFAIK wont buffer your pH. It may however
> contain some amount of calcium carbonate, which does that.
>
> > Any advice or comments would be appreciated. I'd especially like to
here if
> > anyone else has tried this in their own tanks.
>
> Just plunk a couple of limestone rocks and/or a bag of coral sand in
> the filter and/or a couple of seashells in the tank, and your water
> will straighten itself out in a few days to 2 weeks (depending on how
> much you plunk in and in what form).
>
> > p.s. Anyone want to trade some of their hard water for my soft water?
Maybe
> > I should start looking at discus or some other soft water fish.
>
> If you wish, but it's much easier to make soft water hard than to make
> hard water soft...

Thanks for all the responses folks. I appreciate the comments.

On Monday I added a cup (not a measuring cup) of aragonite to the tank.
When I got back last night, the fish seemed more active, and seemed much
less prone to hide behind/in the Java Moss. Unfortunately, I was not able
to get intermediate measurements becasue I had to go out of town, but
tonight, 4 nights later, the water parameters are much better:
pH - 7.4 (was <6.0)
dKH - 3 (was 1 after water change, and 0 before water change)
dGH - 6 (was 3)

The aragonite has definitely done the trick.

My only concern is that the pH changed so fast. The fish seem healthier
than when I left, so I guess it was slow enough for them to tolerate. I
wish I had taken some measurements in the morning and the next evening to
see just how fast things changed.

Oh well... I guess I shouldn't complain since it worked out so well.

Joe

[Dr Engelbert Buxbaum]

Joe Crowder wrote:

> Now having said all that, here are my water parameters as of last night just
> before I did a water change: Ammonia - 0 ppm, Nitrate - 15 ppm, pH - <6
> (bottom of my scale), GH - 3 dGH. Anyone see the problem yet? I'll give
> you another hint. I got a test kit for KH today, and guess what the KH was
> less than 1 dKH. I also tested the tap water this evening: pH - 7.8, GH - 3
> dGH, KH - 3 dGH.

Wonderful soft water for a Southamerican black-water community tank.

>
> So, here is my conclusion: Something (plants, snails, ???) is using up what
> little alkalinity I have in my very soft water to begin with, and my pH is
> crashing. I haven't seen this in my other tank because I have flourite as a
> substrate which is probably acting as a buffer.

Buffering usually comes from carbonate hardness, and you have very
little of that. Add a little acid froom metabolic activity, and pH
drops.

> Based on my reading, and the advice from the LFS (he actually said to skip
> the KH test), the corrective action is to add CaCO3 in the form of aragonite
> (crushed coral), limestone, marble, etc. The CaCO3 which will bring up the
> KH, GH, and pH to a more reasonable level. Adding Baking Soda, would raise
> KH and pH, but not affect GH. I've added a cupful of aragonite to my tank a
> start. Now, I think I am in for some experimenting. I need to figure out
> how much aragonite to use, and how often to replace it. I've started with a
> cupful just thrown on the bottom. I did not wash it because I want the dust
> to dissolve a little quicker to get the whole process started.
>
> Now for my questions:
> 1) Are my conclusions correct?

Do you really want to harden the water? This depends on the fishes you
keep. For black-water fishes I would just use a little peat in the
filter, that will keep the pH around 6.8.

> 2) Is the corrective action I've described correct? Is there a better
> material/process to add CaCO3?

If you have to raise pH, lime stone is fine. Speed of action does not
depend on the amount you put in, but on the surface area (small grains =
faster action).

> 3) Is there any reason to also use baking soda (NaHCO3)?

NO. Baking soda works too fast, stressing your fish. Also, the action is
very temporary.

> 4) Any suggestion on amount of aragonite to use?

As mentioned, the amount is not so important. Just replace it when it
has dissolved.

> 5) Any suggestions on replacement schedule? How long will it last before
> depleting? weeks? months? years?

That depends on the amount you put in, the tank size and the
concentration of acid in your water. But it is no real problem, just add
more when the old stuff is almost gone.

> 6) Could this be some sort of seasonal thing from the city water supply?

Ask the supply company. They keep records on their waters properties.


> p.s. Anyone want to trade some of their hard water for my soft water? Maybe
> I should start looking at discus or some other soft water fish.

Old rule: Match the fish to the water, not the other way round.

[Mean_Chlorine]

Dr Engelbert Buxbaum > wrote in message >...

> > 2) Is the corrective action I've described correct? Is there a better
> > material/process to add CaCO3?
>
> If you have to raise pH, lime stone is fine. Speed of action does not
> depend on the amount you put in, but on the surface area (small grains =
> faster action).

Good point.

> > p.s. Anyone want to trade some of their hard water for my soft water? Maybe
> > I should start looking at discus or some other soft water fish.
>
> Old rule: Match the fish to the water, not the other way round.

Then again, _raising_ pH and hardness is as easy as decorating with some limestone.

[Joe Crowder]

"Dr Engelbert Buxbaum" > wrote in message
->
<snip>
> Wonderful soft water for a Southamerican black-water community tank.
Hmm... What kind of fish come from that environment? I've been thinking
about setting up another tank ;-)

<snip>
>
> Do you really want to harden the water? This depends on the fishes you
> keep. For black-water fishes I would just use a little peat in the
> filter, that will keep the pH around 6.8.
Unfortunately, I decided on Endler's Livebearer's before I understood the
problem. So, I need to increase hardness in this tank or give them up to a
good home. So far, the crushed coral seems to be working our great. So
far, it seems to be a self -regulating, and pretty stable.

<snip>
> Old rule: Match the fish to the water, not the other way round.
Now that I understand a little more practical chemistry, I agree. I this
case, I'll break the rule though.

[Dr Engelbert Buxbaum]

Joe Crowder wrote:

>
> "Dr Engelbert Buxbaum" > wrote in message
> ->
> <snip>
> > Wonderful soft water for a Southamerican black-water community tank.
> Hmm... What kind of fish come from that environment? I've been thinking
> about setting up another tank ;-)

The bug cought you, didn't it?

Tetras, angel fish, corys. Some ghost shrimp (but not together with
angels).

Not from the area, but fitting with the water and quite some characters
would be clown loaches (with the added benefit of eradicating the snails
that often come with plants). Zebra fish also do well in this sort of
environment.

Or, if you want to show off, a tank with pirana.