Whats more important PH or KH

[xtr396472]

I have started to use Flourish Excel to feed my plants instead of DIY yeast
CO2
The only problem is my tap water KH is 3 and pH at least 7.6
What is more important to maintain the pH or the KH. I would like to get the
pH down to around 7 with out using CO2 just for breeding purposes.
Any thought apprec.
Thanks

[Iain Miller]

"xtr396472" > wrote in message
...
> I have started to use Flourish Excel to feed my plants instead of DIY
yeast
> CO2
> The only problem is my tap water KH is 3 and pH at least 7.6
> What is more important to maintain the pH or the KH. I would like to get
the
> pH down to around 7 with out using CO2 just for breeding purposes.
> Any thought apprec.
> Thanks

The two are linked. At a known level of CO2 (i.e. what you get from the
Atmosphere) as KH falls so Ph will fall with it. In other words if you want
to bring down the Ph to 7 then you need to reduce the Kh which you can do
with Peat, or bogwood etc.

However, two issues...

a) As Kh approaches zero so Ph becomes unstable and can crash (to 5 & below)
with disasterous results.

b) At levels below Kh 3-4 you get Ammonium instead of Ammonia released. This
means your Bio filter dies back a bit. If you then bring the Kh back up to 4
& above for any reason the Ammonia suddenly gets released as Ammonia with
similarly diasterous consequences - this one is known as "Old Tank Syndrome"
since over time the Kh of a tank will naturally fall (unless there is
anything in the tank to hold it up). With a tank like that if you then do a
water change and so restore the Kh everything can go a bit pear shaped.

Safest way to bring Ph down to 7 & below is with CO2.

rgds

I.

[NetMax]

"Iain Miller" > wrote in message
...
>
> "xtr396472" > wrote in message
> ...
> > I have started to use Flourish Excel to feed my plants instead of DIY
> yeast
> > CO2
> > The only problem is my tap water KH is 3 and pH at least 7.6
> > What is more important to maintain the pH or the KH. I would like to
get
> the
> > pH down to around 7 with out using CO2 just for breeding purposes.
> > Any thought apprec.
> > Thanks
>
> The two are linked. At a known level of CO2 (i.e. what you get from the
> Atmosphere) as KH falls so Ph will fall with it. In other words if you
want
> to bring down the Ph to 7 then you need to reduce the Kh which you can
do
> with Peat, or bogwood etc.

Does the kH drop significantly with CO2 injection? My understanding was
that the pH dropped with CO2 injection because the kH didn't. On the
other hand, CO2 makes carbonic acid which would drop your kH.

> However, two issues...
>
> a) As Kh approaches zero so Ph becomes unstable and can crash (to 5 &
below)
> with disasterous results.
>
> b) At levels below Kh 3-4 you get Ammonium instead of Ammonia released.
This
> means your Bio filter dies back a bit. If you then bring the Kh back up
to 4
> & above for any reason the Ammonia suddenly gets released as Ammonia
with
> similarly diasterous consequences - this one is known as "Old Tank
Syndrome"
> since over time the Kh of a tank will naturally fall (unless there is
> anything in the tank to hold it up). With a tank like that if you then
do a
> water change and so restore the Kh everything can go a bit pear shaped.

I thought the NH4 to NH3 conversion was a direct function of only pH.
Under acidic forces, the kH will indirectly alter the NH3 to NH4 by
allowing the pH to drop (but I'm no chemist).
--
www.NetMax.tk

> Safest way to bring Ph down to 7 & below is with CO2.
>
> rgds
>
> I.

[Kris]

> The two are linked. At a known level of CO2 (i.e. what you get from the
> Atmosphere) as KH falls so Ph will fall with it. In other words if you want
> to bring down the Ph to 7 then you need to reduce the Kh which you can do
> with Peat, or bogwood etc.
>
> However, two issues...
>
> a) As Kh approaches zero so Ph becomes unstable and can crash (to 5 & below)
> with disasterous results.



I do and don't agree with the above statements.

IIRC
a high KH (>70 ppm) will raise pH, but KH, within normal ranges, acts as
a stabilizer (buffer) for pH, the lower the KH the more drastic the pH
swings maybe. An average KH 30-70 ppm will keep large (rapid) pH swings
from happening due to outside factors. A KH of lower than average can
allow pH swings caused by something as simple as the aquariums lights
on/off cycle.

any chemists out there that can translate that into a more
understandable language?

I used to work as a swimming pool technician, so if my chemistry is off,
think twice before going into a public pool.

Kris

[[email protected]]

"xtr396472" > wrote in message >...
> I have started to use Flourish Excel to feed my plants instead of DIY yeast
> CO2
> The only problem is my tap water KH is 3 and pH at least 7.6
> What is more important to maintain the pH or the KH. I would like to get the
> pH down to around 7 with out using CO2 just for breeding purposes.
> Any thought apprec.
> Thanks

As far a breeding goes, the KH, the salts etc in your water are more
important.
I do not consider pH to be a large issue except with repsect to
measuring CO2 with KH.
Fish live in wide ranges and I think people worry too much about it
and think having it at some precise range is best. pH changes daily in
regions where there are both plants and fish. Often quite large
variations.

If you sit your tap water out in a glass for 24 hours and then measure
the pH what do you think it will be? About 7.2-7.3 or so. Try it and
see.

Good plant growth = good fish health.

I do not think it will make any difference in your tank or breeding to
have a pH of 7.0 vs 7.4.

You can use peat
You can use CO2
Excel is okay, but it's maybe 1/3 the potency of CO2 gas.
DIY is cheap.

I'd stick with CO2 personally. I have fish breed all the time and I
don't worry about the fish at all, just take care of the plants and
feeded a varied diet to the fish.

Fish are secondary to me, you might not feel the same, but the
approach of taking care of the plants to take care of the fish does
work very well FYI.

Regards,
Tom Barr

[Iain Miller]

> > The two are linked. At a known level of CO2 (i.e. what you get from the
> > Atmosphere) as KH falls so Ph will fall with it. In other words if you
> want
> > to bring down the Ph to 7 then you need to reduce the Kh which you can
> do
> > with Peat, or bogwood etc.
>
> Does the kH drop significantly with CO2 injection? My understanding was
> that the pH dropped with CO2 injection because the kH didn't. On the
> other hand, CO2 makes carbonic acid which would drop your kH.

No, CO2 doesn't touch Kh it reduces Ph


> I thought the NH4 to NH3 conversion was a direct function of only pH.
> Under acidic forces, the kH will indirectly alter the NH3 to NH4 by
> allowing the pH to drop (but I'm no chemist).

I'm no chemist either (!) I just know that at low levels of Kh you can run
into OTS if you arn't careful - its not likely to be an issue if the water
you use for changes has the same Kh as the water in the tank - its when the
new water is much harder that the problem emerges AIUI. Hence why "Old tank
syndrome" tends to happen to people who use tap water in their tanks & don't
change any for ages.

I.

[Iain Miller]

"Kris" > wrote in message
news:bebzc.18815$lN.13766@edtnps84...
> > The two are linked. At a known level of CO2 (i.e. what you get from the
> > Atmosphere) as KH falls so Ph will fall with it. In other words if you
want
> > to bring down the Ph to 7 then you need to reduce the Kh which you can
do
> > with Peat, or bogwood etc.
> >
> > However, two issues...
> >
> > a) As Kh approaches zero so Ph becomes unstable and can crash (to 5 &
below)
> > with disasterous results.
>
> I do and don't agree with the above statements.
>
> IIRC
> a high KH (>70 ppm) will raise pH, but KH, within normal ranges, acts as
> a stabilizer (buffer) for pH, the lower the KH the more drastic the pH
> swings maybe. An average KH 30-70 ppm will keep large (rapid) pH swings
> from happening due to outside factors. A KH of lower than average can
> allow pH swings caused by something as simple as the aquariums lights
> on/off cycle.

You are right in that the relationship between Kh & Ph is not linear
(there's a log in the formula somewhere!) - I've got a spreadsheet that
works it out somewhere. Kh has to get pretty close to zero before Ph starts
to really crash but as it gets closer the decline in Ph definitly
accelerates. The OP was talking about wanting a Ph of around 7 - according
to what I have at atmosphesric levels of CO2 (3ppm roughly) that would
require a Kh of about 1dKh (15-17ppm) which is still stable & maintanable
but doesn't leave much room for error - its getting pretty close to zero
IMO.

I.

[Bob]

"xtr396472" > wrote in message
...
> I have started to use Flourish Excel to feed my plants instead of DIY
yeast
> CO2
> The only problem is my tap water KH is 3 and pH at least 7.6
> What is more important to maintain the pH or the KH. I would like to get
the
> pH down to around 7 with out using CO2 just for breeding purposes.
> Any thought apprec.
> Thanks
>
>

pre-filtering thru peat will work for sure.
It is far easier and cheaper then co2, the only downside, is it is a little
messier.

Bob

[Iain Miller]

"Bob" > wrote in message
...
> "xtr396472" > wrote in message
> ...
> > I have started to use Flourish Excel to feed my plants instead of DIY
> yeast
> > CO2
> > The only problem is my tap water KH is 3 and pH at least 7.6
> > What is more important to maintain the pH or the KH. I would like to get
> the
> > pH down to around 7 with out using CO2 just for breeding purposes.
> > Any thought apprec.
> > Thanks
> >
> >
>
> pre-filtering thru peat will work for sure.
> It is far easier and cheaper then co2, the only downside, is it is a
little
> messier.

Indeed it will (I do it).

Its important for the OP to understand what goes on there though....it
lowers the Ph because it eats up the Kh. There's an added twist to it in
that when you prefilter through peat you also get a LOT of CO2 in the water
initially. This "out-gasses" in a few hours but the key to doing this and
knowing where you are is therefore not to measure Ph but to track Kh as you
are filtering the water. This is because the Ph will be artificially low on
account of the excess CO2 that gets into the water during the filtering
process. I've meaured it (by measuring Ph and Kh & reading off the relevant
tables) at over 120ppm straight out the peat filter.

I.

[NetMax]

"Iain Miller" > wrote in message
news:eEMzc.219$yi3.96@newsfe4-gui...
>
> "Bob" > wrote in message
> ...
> > "xtr396472" > wrote in message
> > ...
> > > I have started to use Flourish Excel to feed my plants instead of
DIY
> > yeast
> > > CO2
> > > The only problem is my tap water KH is 3 and pH at least 7.6
> > > What is more important to maintain the pH or the KH. I would like
to get
> > the
> > > pH down to around 7 with out using CO2 just for breeding purposes.
> > > Any thought apprec.
> > > Thanks
> > >
> > >
> >
> > pre-filtering thru peat will work for sure.
> > It is far easier and cheaper then co2, the only downside, is it is a
> little
> > messier.
>
> Indeed it will (I do it).
>
> Its important for the OP to understand what goes on there though....it
> lowers the Ph because it eats up the Kh. There's an added twist to it
in
> that when you prefilter through peat you also get a LOT of CO2 in the
water
> initially. This "out-gasses" in a few hours but the key to doing this
and
> knowing where you are is therefore not to measure Ph but to track Kh as
you
> are filtering the water. This is because the Ph will be artificially
low on
> account of the excess CO2 that gets into the water during the filtering
> process. I've meaured it (by measuring Ph and Kh & reading off the
relevant
> tables) at over 120ppm straight out the peat filter.
>
> I.

A little OT, but I read an article that implied that peat had some
buffering qualities. In the case where the tap water was kH-poor (ie: 2
dkH, low gH, but high pH), using peat to lower the pH worked better than
other methods (CO2 injection, RO, DI, acids etc). The author didn't
expand further, so I'm uncertain if there is any validity to this, and if
there are particular circumstances where it's applicable.

It would be nice to have something which would gently drop *and*
stabilize the pH in the high 6s or low 7s.
--
www.NetMax.tk

[xtr396472]

I still have a high ph after 24 hours 7.6 plus
Thanks for all the answers
Mike




" > wrote in message
m...
> "xtr396472" > wrote in message
>...
> > I have started to use Flourish Excel to feed my plants instead of DIY
yeast
> > CO2
> > The only problem is my tap water KH is 3 and pH at least 7.6
> > What is more important to maintain the pH or the KH. I would like to get
the
> > pH down to around 7 with out using CO2 just for breeding purposes.
> > Any thought apprec.
> > Thanks
>
> As far a breeding goes, the KH, the salts etc in your water are more
> important.
> I do not consider pH to be a large issue except with repsect to
> measuring CO2 with KH.
> Fish live in wide ranges and I think people worry too much about it
> and think having it at some precise range is best. pH changes daily in
> regions where there are both plants and fish. Often quite large
> variations.
>
> If you sit your tap water out in a glass for 24 hours and then measure
> the pH what do you think it will be? About 7.2-7.3 or so. Try it and
> see.
>
> Good plant growth = good fish health.
>
> I do not think it will make any difference in your tank or breeding to
> have a pH of 7.0 vs 7.4.
>
> You can use peat
> You can use CO2
> Excel is okay, but it's maybe 1/3 the potency of CO2 gas.
> DIY is cheap.
>
> I'd stick with CO2 personally. I have fish breed all the time and I
> don't worry about the fish at all, just take care of the plants and
> feeded a varied diet to the fish.
>
> Fish are secondary to me, you might not feel the same, but the
> approach of taking care of the plants to take care of the fish does
> work very well FYI.
>
> Regards,
> Tom Barr