buffering ph by adding minerals

[chris nuttall]

i know you can add various things to your water to buffer the ph
towards a certain value, that value being different depending exactly
which mineral(s) you add, but does anyone know what will buffer to a
ph of 7?
Sodium bicarb buffers to around 8 i think
coral to around 8.2 ish
limestone...not sure

I did try evian! its got 360ppm bicarbonates (kh) and is ph 7.2, so
you can add as much as you need to achieve any kh you want, but its
effects seem to be temporary, and i think i need to add a solid so
that it can slowly dissolve.....but what to add?

chris

[RedForeman ©®]

|| i know you can add various things to your water to buffer the ph
|| towards a certain value, that value being different depending exactly
|| which mineral(s) you add, but does anyone know what will buffer to a
|| ph of 7?
|| Sodium bicarb buffers to around 8 i think
|| coral to around 8.2 ish
|| limestone...not sure

These numbers are relative to the water you start with.... if you're
starting with 7.0 water, adding baking soda can acheive 8.0, so if you want
7, and a kH of 3 or so, maybe adding CO2 which will bring back your pH to
7.2 or so...

I've used baking soda and CO2 to maintain a 7.0 tank for almost 2 years...
always stable

I've heard crushed coral, limestone, and marble chips are all good to use..

|| I did try evian! its got 360ppm bicarbonates (kh) and is ph 7.2, so
|| you can add as much as you need to achieve any kh you want, but its
|| effects seem to be temporary, and i think i need to add a solid so
|| that it can slowly dissolve.....but what to add?
||
|| chris

What is your water to start with??

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[Bill Stock]

"chris nuttall" > wrote in message
om...
> i know you can add various things to your water to buffer the ph
> towards a certain value, that value being different depending exactly
> which mineral(s) you add, but does anyone know what will buffer to a
> ph of 7?
> Sodium bicarb buffers to around 8 i think
> coral to around 8.2 ish
> limestone...not sure
>
> I did try evian! its got 360ppm bicarbonates (kh) and is ph 7.2, so
> you can add as much as you need to achieve any kh you want, but its
> effects seem to be temporary, and i think i need to add a solid so
> that it can slowly dissolve.....but what to add?
>
> chris

I think Red pretty much covered all the bases.

I had a PH crash a while ago and tried a few products. I tried the lawn lime
(not slaked) first and it was OK, but it was messy. I also tested some
limestone screenings (meant for under patio stones), which worked better
(faster) then the lawn lime, but had to be thoroughly washed, as it
contained a lot of contaminants. Finally, ended up using the crushed coral
in my filter, as it was cleaner and fast acting. My KH is around 150 and PH
stays around 7.5 using the coral. My test samples of lawn lime and limestone
screenings were somewhere around 7.8 after a week.

[chris nuttall]

my tap water is ph 7 with a kh of 11 degrees
my tank water is also ph 7 with a maximum kh of 8 or 9 (it keeps
dropping see my other post called ph kh snails and clown loach)
i get falling kh and ultimately ph, so i want to add buffering
capacity to the water to maintain ph 7.0 if possible, but i am worried
that coral will buffer it up to 8 ish.....i just dont want to kill any
fish by experimenting.

chris

[RedForeman ©®]

|| my tap water is ph 7 with a kh of 11 degrees
|| my tank water is also ph 7 with a maximum kh of 8 or 9 (it keeps
|| dropping see my other post called ph kh snails and clown loach)
|| i get falling kh and ultimately ph, so i want to add buffering
|| capacity to the water to maintain ph 7.0 if possible, but i am
|| worried that coral will buffer it up to 8 ish.....i just dont want
|| to kill any fish by experimenting.
||
|| chris

1. Most fish will adjust to whatever water you have... that being said...
let's move on..
2. pH doesn't harm fish unless it changes quickly or dramatically... pH
swings as they are called, is more dangerous than just keeping a different
pH than a fish starts out in...
3. Unless you're actively breeding, a pH between 6.5 and 7.5 isn't bad for
alot of fish...I've kept guppies in both extremes, you get females with a
lower pH and males with a higher pH...
4 for a planted tank, your pH and kH give you a CO2 level of 33ppm which
seems erroneous... are you injecting CO2 at all?

If you have a 7.0 tank, and 11kH I'd be happy with it... I'd just settle on
a weekly routine of doing a water change and adding a teaspoon of sodium
bicarbonate (*baking soda*) to it as a buffer... that will raise your pH to
7.4, but it ultimately won't drop as fast as before... giving you a certain
time frame to work with....

Peat can lower your pH, and soften it I believe.. then adding the baking
soda as the buffer can acheive your desired affect, it is a bit of trouble
though...

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[Bill Stock]

"chris nuttall" > wrote in message
om...
> my tap water is ph 7 with a kh of 11 degrees
> my tank water is also ph 7 with a maximum kh of 8 or 9 (it keeps
> dropping see my other post called ph kh snails and clown loach)
> i get falling kh and ultimately ph, so i want to add buffering
> capacity to the water to maintain ph 7.0 if possible, but i am worried
> that coral will buffer it up to 8 ish.....i just dont want to kill any
> fish by experimenting.
>
> chris

Chris,

You should be OK with coral. Add a small amount, say a cup per 10 gallons
and test daily. If your KH is not satisfactory after a week (too low), add
more coral.

My tap water is very similar to yours, but my PH WAS falling below 6, even
with weekly water changes. I had 'old tank syndrome' sneak up on me. I added
about four cups of coral to my 55 gallon and my KH has stayed around 150 and
my PH is between 7 and 7.5. It's never been anywhere near 8, but I do weekly
water changes as I said.

[NetMax]

"RedForeman ©®" > wrote in message
...
<snip>

> 3. Unless you're actively breeding, a pH between 6.5 and 7.5 isn't bad
for
> alot of fish...I've kept guppies in both extremes, you get females with
a
> lower pH and males with a higher pH...

I'd heard about Krib fry being influenced by pH, but not Guppies, however
I have Guppies in one of my tanks (8.4pH), and I noticed today that it's
currently an all-male population. I can't vouch for more males than
females being born (though it seems that way), but the females *have*
been much more short lived than the males. I think 8.4pH is outside
their limits. Perhaps I'll switch to other fry-generators like Mollys,
Swordtails or even Platys as they all seemed more tolerant of the high
pH.
--
www.NetMax.tk

<snip>
>
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>
>

[chris nuttall]

what is 'old tank syndrome'?

chris

[chris nuttall]

about the co2 level; i do not inject co2, there is an air pump running
(which should have the opposite effect i think). The ph and kh only
start at those values, they soon fall to much lower levels.
for 2 years there was no problem, its only recently started happening
(co-incidentally at the same time i started getting a lot of snails, i
wonder if they could be robbing the water of bicarbonates?)

i have tried bicardonate of soda, the ph and kh still fall, they just
start from a higher value, i tried evian too, with the same result.
i think i should get some coral, then as it dissolves there will be
more 'in reserve'

chris

[Mean_Chlorine]

Thusly (chris nuttall) Spake Unto All:

>what is 'old tank syndrome'?

Never heard of it in freshwater, but in sal****er it is an observation
that after several years of flawless operation aquaria tend to slowly
decline. "Restarting" the aquarium with fresh live rock and sand
brings it back on track. Ron Shimek has propsed that OTS is caused by
heavy metal build-up in the rockwork - at the pH's seen in marine
aquaria, the heavy metals found as contaminants in the salt mix
precipitate on limestone.

[Mean_Chlorine]

Thusly (chris nuttall) Spake Unto All:

>(which should have the opposite effect i think). The ph and kh only
>start at those values, they soon fall to much lower levels.

Do you trust your kits, though? The reaction chemicals have a shelf
life of perhaps a year.

>i have tried bicardonate of soda, the ph and kh still fall, they just
>start from a higher value, i tried evian too, with the same result.

Evian is essentially bicarbonate dissolved in water with some salt
added, so it's the same thing. Adding bicarbonate in any form is a
temporary fix, as the tank will eventually equilibrate with the
atmosphere by releasing CO2, and the KH drops again.

I don't remember what pH/KH you want, but if pH 7.5 is acceptable to
you, just plonk in some limestone. Crushed coral, seashells, even
cuttlefish bone or eggshell will work too, and you can if you want put
them in a bag in your filter. But the easiest is just to decorate the
tank with limestone. Limestone will raise KH and pH and lock pH at
7.5.

>i think i should get some coral, then as it dissolves there will be
>more 'in reserve'

That will work yes.

>chris

[NetMax]

"chris nuttall" > wrote in message
om...
> what is 'old tank syndrome'?
>
> chris

Basically, everything organic (uneaten food, fish waste, dead plant
matter etc) slowly gets broken down by bacteria releasing ammonia, and
acidifying the water (by first reducing your buffer and then reducing
your pH). Under normal conditions, this extra ammonia is consumed by
nitrifying bacteria and the acidifying effect is absorbed by your water's
buffer (also known as the karbonate hardness or kH). The buffer is
replenished by routine water changes.

In tanks which have been running a long time and/or haven't been properly
maintained, this dissolving organic matter (detritus or mulm) accumulates
in the gravel and its effects begin overtaking the aquarium system's
ability to cope with them. In hard-water tanks, this manifests itself as
very high and persistent nitrates (NO3). In all other tanks, OTS
manifests itself by extremely and persistently low pH.

You can detect the onset of OTS in most tanks by measuring to see if
there is a significant difference between your source water kH and your
tank water kH (usually measured in degrees or dkH, ie: under 2dkH =
danger, under 4dkH = caution - dependant on application). hth

http://www.2cah.com/netmax/basics/water/water.shtml#ots

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[RedForeman ©®]

|| about the co2 level; i do not inject co2, there is an air pump
|| running (which should have the opposite effect i think). The ph and
|| kh only start at those values, they soon fall to much lower levels.
|| for 2 years there was no problem, its only recently started happening
|| (co-incidentally at the same time i started getting a lot of snails,
|| i wonder if they could be robbing the water of bicarbonates?)

Not likely...

|| i have tried bicardonate of soda, the ph and kh still fall, they just
|| start from a higher value, i tried evian too, with the same result.
|| i think i should get some coral, then as it dissolves there will be
|| more 'in reserve'
||
|| chris

I'm leaning towards a bad test kit... how old are they?

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[chris nuttall]

the test kit is a strip with multiple tests on it, there is a pot of
25 and i have been testing quite frequently lately, so they are only a
few weeks old.
I think that the falling kh and ph are real, after a waterchange the
values are normal, and as i test during the next week the kh slowly
drops, and once it reaches 3 or 4 then the ph starts to drop too, then
if i let it go on, i come downstairs one morning to dead fish (i guess
the ph drops further during the hight due to the respiration of the
plants).

the question is why is it happening.

the tank is not over stocked, i dont think i overfeed, i do a partial
waterchange every week, the tap water is reasonble, and it is stable
over a week or more if left in a glass.

The only thing which is out of the ordinary is the number of these
snails in the gravel, there are hundreds of them. I have a lot of
bottom feeders so much of the food ends up on the substrate, which is
why i suppose the snails get anything to eat. The guy in the lfs
thinks the number of snails could be taking my modest stocking level
up to the limit, both in terms of C02 emmitted, and of amonia
produced- both of these thinks produce acid. I am declairing war on
the snails, and if it turns out not to be their fault, then they can
form a terrorist cell in the uk and side with all of the other
needlessly persecuted populations of the world.....i think this is
beginning to get to me!!!


chris

[RedForeman ©®]

|| The only thing which is out of the ordinary is the number of these
|| snails in the gravel, there are hundreds of them. I have a lot of
|| bottom feeders so much of the food ends up on the substrate, which is
|| why i suppose the snails get anything to eat. The guy in the lfs
|| thinks the number of snails could be taking my modest stocking level
|| up to the limit, both in terms of C02 emmitted, and of amonia
|| produced- both of these thinks produce acid. I am declairing war on
|| the snails, and if it turns out not to be their fault, then they can
|| form a terrorist cell in the uk and side with all of the other
|| needlessly persecuted populations of the world.....i think this is
|| beginning to get to me!!!
||
|| chris

I don't buy into that, because, my 10g, only has 2 kribs, 3 kuhlis, and a
bristlenose in it, planted, and it's got well over several thousand MTS and
I maintain a healthy 7.2pH and kH of 3 using ONLY black onyx sand... hmmm

We've never discussed what substrate you have.... what ARE you using?

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[chris nuttall]

> I don't buy into that, because, my 10g, only has 2 kribs, 3 kuhlis, and a
> bristlenose in it, planted, and it's got well over several thousand MTS and
> I maintain a healthy 7.2pH and kH of 3 using ONLY black onyx sand... hmmm
>
> We've never discussed what substrate you have.... what ARE you using?



it's plain old gravel, roughly 1/4" in size. I recently (like two
weeks ago) removed half of it, so it is now about 1" deep. Less for
the snails to live in.
I siphon the gravel well every time i do a w/c (which is currently
weekly)

I have heard that bog wood can lower the ph, but i dont know how, or
how vigerous it is. There is a 9" long bit in there for the
bristlenoses(apparently there is a theory that munching on it is
essential to their diet - they do munch on it too, they also spawn
regularly under it) -could this be the trouble? It has been in the
tank since day one - 3 years now, never a problem before......

I have also heard that mature sword plants which grow vigerously
(again - i have one) can de-calcify the water, causing a kh drop, but
i dont know how serious it is.....

The latest thing to happen in this tale of woe is a mild outbreak of
ich, i have spotted it early and am treting with a formaldahide based
product. I think the ph droips are ****ing the fish off somewhat!

at a loss.....

chris

[RedForeman ©®]

||| I don't buy into that, because, my 10g, only has 2 kribs, 3 kuhlis,
||| and a bristlenose in it, planted, and it's got well over several
||| thousand MTS and I maintain a healthy 7.2pH and kH of 3 using ONLY
||| black onyx sand... hmmm
|||
||| We've never discussed what substrate you have.... what ARE you
||| using?
||
|| it's plain old gravel, roughly 1/4" in size. I recently (like two
|| weeks ago) removed half of it, so it is now about 1" deep. Less for
|| the snails to live in.
|| I siphon the gravel well every time i do a w/c (which is currently
|| weekly)

regular gravel is inert... and disturbing the gravel can lead to some
nasties getting into the water, which you already see/smell...

|| I have heard that bog wood can lower the ph, but i dont know how, or
|| how vigerous it is. There is a 9" long bit in there for the
|| bristlenoses(apparently there is a theory that munching on it is
|| essential to their diet - they do munch on it too, they also spawn
|| regularly under it) -could this be the trouble? It has been in the
|| tank since day one - 3 years now, never a problem before......

I think the driftwood/bogwood soften the water, not sure they actually lower
pH...

|| I have also heard that mature sword plants which grow vigerously
|| (again - i have one) can de-calcify the water, causing a kh drop, but
|| i dont know how serious it is.....

First time I've ever heard that....

|| The latest thing to happen in this tale of woe is a mild outbreak of
|| ich, i have spotted it early and am treting with a formaldahide based
|| product. I think the ph droips are ****ing the fish off somewhat!

I can see where you'd be frustrated.... Can I offer a totally off the wall
beginning step to a possible end result type of solution??

1. Identify what pH you'd like to target... Lets use 7.0 for starters..Make
your ritual waterchanges as normal, possibly adding baking soda to buffer up
to 7.6 or so...(btw, 7.0 is ok for 90% of fish), since your doing weely w/c,
it won't run out in a week. That should stabilize your buffer, and help
maintain a rock solid pH... if it does drop, try option 2.

2. Add some crushed coral to a used pair of pantyhose and drop it in the
back of your filter(after rinsing thoroughly). Double bagging might make it
too hard to leech, so maybe one single wrapping will suffice...

What that will aid in, is to release or dissolve a bit at a time and help
keep your pH more stable than sodium bicarb...and, btw, snails use calcium
bicarb, that's what their shells are made of, so they can't really 'rob' you
of anything.... you could take a look at them to see if the tips of their
shells are turning white, that would mean there is a shortage in the first
place...

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[chris nuttall]

> 1. Identify what pH you'd like to target... Lets use 7.0 for starters..Make
> your ritual waterchanges as normal, possibly adding baking soda to buffer up
> to 7.6 or so...(btw, 7.0 is ok for 90% of fish), since your doing weely w/c,
> it won't run out in a week. That should stabilize your buffer, and help
> maintain a rock solid pH... if it does drop, try option 2.

already tried that and it does drop


>
> 2. Add some crushed coral to a used pair of pantyhose and drop it in the
> back of your filter(after rinsing thoroughly). Double bagging might make it
> too hard to leech, so maybe one single wrapping will suffice...




i bought the coral and put it in and old stocking, but i have taken it
out while i treat the ich for two reasons, first just in case it
absorbs the medicine, and also because i have to do a w/c every four
days anyway while i treat the fish......but i will put it back and see
if it works.


>
> What that will aid in, is to release or dissolve a bit at a time and help
> keep your pH more stable than sodium bicarb...and, btw, snails use calcium
> bicarb


i didnt know that...thanks!


, that's what their shells are made of, so they can't really 'rob' you
> of anything....


is calcium bicarbonate not a ph buffer then?....it must be present in
the tap water to enable the snails to grow their shells in the first
place......the coral is made of the same compound right? so that will
be a direct replacement for the useage of the snails?


you could take a look at them to see if the tips of their
> shells are turning white, that would mean there is a shortage in the first
> place...



no, they are lovely and healthy!



chris

[RedForeman ©®]

|| is calcium bicarbonate not a ph buffer then?....it must be present in
|| the tap water to enable the snails to grow their shells in the first
|| place......the coral is made of the same compound right? so that will
|| be a direct replacement for the useage of the snails?

of course your tap water DOES contain calcium if it's city water... well
water doesn't... But the levels of calcium are so extremely low, almost
undetectable by a test kit... You might have higher levels if your coffee
pot gets a white crusty rim, that's a calcium deposit... if you have softer
water, less likely you have calcium...

|| you could take a look at them to see if the tips of their
||| shells are turning white, that would mean there is a shortage in
||| the first place...
||
|| no, they are lovely and healthy!
||

Then your levels of calcium are low enough to not leave calcium rings on
your tank, but high enoug that keeps the snails good and shiny...

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[RedForeman ©®]

|| is calcium bicarbonate not a ph buffer then?....it must be present in
|| the tap water to enable the snails to grow their shells in the first
|| place......the coral is made of the same compound right? so that will
|| be a direct replacement for the useage of the snails?

Calcium carbonate is an additive, mainly used for reef tanks, helps keep the
corals and shell animals healthy, and no, it's not actually a buffer... what
*is* a buffer is sodium carbonate..aka.. baking soda.. Arm&Hammer....

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[Mean_Chlorine]

Thusly "RedForeman ©®" > Spake Unto All:

>Calcium carbonate is an additive, mainly used for reef tanks, helps keep the
>corals and shell animals healthy, and no, it's not actually a buffer... what
>*is* a buffer is sodium carbonate..aka.. baking soda.. Arm&Hammer....

Calcium carbonate is an almost insoluble solid, aka limestone.
Bicarbonate is the same as KH, although in marine water carbonate
matters too.

Limestone, when subjected to any pH below about 8.3, will dissolve
into free calcium ions and, yes, bicarbonate. So limestone is a
buffer, just not a fast-acting one, as it's a solid with poor
solubility, but it will dissolve, and it will buffer pH. The
solubility of limestone is pH dependent, so at very low pH it will
dissolve relatively rapidly (try dropping acid on a limestone),
whereas at pH's above 7.5 the dissolution is so slow as to make no
difference.

Baking soda (which, incidentally, you should make sure is pure sodium
bicarbonate and not added with biphosphate and starch) is sodium
bicarbonate, and easily soluble. That means that it instantly buffs up
the alkalinity of the water (aka "KH"), and hence buffers the pH.

Bicarbonate on its own will tend to push the pH to 8.3. No matter what
the starting pH, and no matter how much you add, the pH will move
towards 8.3 upon addition of bicarbonate.

The downside with bicarbonate is that, since it is easily soluble, you
can raise the pH *very quickly*, which is not always desirable, and,
since there's no slowly dissolving deposit, the pH can drop just as
quickly when the bicarbonate is used up (converted to carbon dioxide
and degassed or used up by plants directly).

Limestone therefore offer a slower and far more long-lasting way of
shoring up pH, and will also raise the pH to a lower maximum than
bicarbonate will.

To be sure bicarbonate has its uses, but most of the time it's
actually easier to just plonk in a couple of limestones. Or put a bag
of seashells in the filter.

[chris nuttall]

thanks for all the info, i am very grateful!......it is sometimes
difficult to piece together all the bits and pieces available on the
web to make perfect sense, in order to come up with the right thing to
do!

chris

[sophie]

In message >, Mean_Chlorine
> writes
>Thusly "RedForeman ©®" > Spake Unto All:
>
>>Calcium carbonate is an additive, mainly used for reef tanks, helps keep the
>>corals and shell animals healthy, and no, it's not actually a buffer... what
>>*is* a buffer is sodium carbonate..aka.. baking soda.. Arm&Hammer....
>
>Calcium carbonate is an almost insoluble solid, aka limestone.
>Bicarbonate is the same as KH, although in marine water carbonate
>matters too.
>
>Limestone, when subjected to any pH below about 8.3, will dissolve
>into free calcium ions and, yes, bicarbonate. So limestone is a
>buffer, just not a fast-acting one, as it's a solid with poor
>solubility, but it will dissolve, and it will buffer pH. The
>solubility of limestone is pH dependent, so at very low pH it will
>dissolve relatively rapidly (try dropping acid on a limestone),
>whereas at pH's above 7.5 the dissolution is so slow as to make no
>difference.
>
>Baking soda (which, incidentally, you should make sure is pure sodium
>bicarbonate and not added with biphosphate and starch) is sodium
>bicarbonate, and easily soluble. That means that it instantly buffs up
>the alkalinity of the water (aka "KH"), and hence buffers the pH.
>
>Bicarbonate on its own will tend to push the pH to 8.3. No matter what
>the starting pH, and no matter how much you add, the pH will move
>towards 8.3 upon addition of bicarbonate.
>
>The downside with bicarbonate is that, since it is easily soluble, you
>can raise the pH *very quickly*, which is not always desirable, and,
>since there's no slowly dissolving deposit, the pH can drop just as
>quickly when the bicarbonate is used up (converted to carbon dioxide
>and degassed or used up by plants directly).
>
>Limestone therefore offer a slower and far more long-lasting way of
>shoring up pH, and will also raise the pH to a lower maximum than
>bicarbonate will.
>
>To be sure bicarbonate has its uses, but most of the time it's
>actually easier to just plonk in a couple of limestones. Or put a bag
>of seashells in the filter.

do they _have_ to go in the filter? I was wondering about raising
hardness the other week, and have put seashells into the tank. My filter
is one of those internals that you stick to the back of the tank (eheim
aquaball) and I'm not sure where i's put the seashells in it...
>

--
sophie

[Mean_Chlorine]

Thusly sophie > Spake
Unto All:

>>To be sure bicarbonate has its uses, but most of the time it's
>>actually easier to just plonk in a couple of limestones. Or put a bag
>>of seashells in the filter.
>
>do they _have_ to go in the filter?

No, you can put it anywhere. But in the filter they're getting better
exposure to the water, hence dissolve faster, hence raise pH/KH
faster.