Newbie and frustrated

On Fri, 18 Mar 2005 17:34:15 GMT, (~Roy~) wrote:

Why does your pond spike so high in PH..........

I have cement blocks around the edge, last year was the worst and they were
5 years old by that time, acid washed many times too. Don't know what the
deal was. Lots of baking soda and water changes took care of it. ~ jan

~Power to the Porg, Flow On!~

George wrote:
"Elaine T" wrote in message
om...

George wrote:

"Sean Dinh" wrote in message
...


TT and nitrate reduction...
http://tinyurl.com/4hlhx


10 ppm is not acceptable in reef aquariums, and I strongly suspect it does
little good in large freshwater systems (such as garden ponds) with
no/inadequate plants to remove it. Hence, the algae blooms. In a sand bed
that uses a Jaubert plenum, a porous plenum is constructed beneath the bed
with a void space below the bed that is filled with water, anaerobic bacteria
form in the bottom depths of the substrate and in the water below. As
anaerobic bacteria cultivate, they remove nitrates. Anaerobic action produces
a fair amount of heat. The heat warms the water layer below the gravel. The
warmer water flows upwards, displacing cooler water above the gravel. This
action moves water through the plenum at very slow rates. The slow movement
of water through the gravel helps to prevent dangerous hydrogen-sulfide gases
from forming in the plenum. The deep gravel bed also provides a home for
burrowing motile invertebrates which feed on solid organic mulm and detritus.
The idea here is to move away from systems that required heavy maintenance to
prevent nitraqtes from getting too high. Trickle filters work great in
removing nitrogen compounds over a limited time period before they must be
maintained (i.e., cleaning pre-filters, etc). Sand beds with a Jaubert
plenum usually never have to be cleaned because, if it is properly
constructed, there is no build up.

http://www.practicalfishkeeping.co.u...?article_id=21

Jaubert plenums have been tried in large FW planted tanks shortly after they
became popular in sal****er. It is much harder to get a population of
denitrifying bacteria in FW that does not include sulfur reducing bacteria and
generally attempts at denitrification in FW crash and burn. Sulfur reducing
bacteria establish in the plenum, poison the water, and fish start showing all
sorts of bizarre diseases in what otherwise seems to be a healthy system.

--
__ Elaine T __
__' http://eethomp.com/fish.html '__


Do you have a link to any papers on this? I found a web site this evening that
describes the set up and it seems to suggest that it works very well, at least
in freshwater aquariums. It also recommended to use 2-3 mm diameter gravel
instead of sand. Since we are talking about a lot more water, I am considering
using even larger gravel (probably something slightly smaller than peah gravel).
I've also read elsewhere that fears of crashing and burning are unfounded if it
is done properly. Of course, like any experiment, I'll have to monitor it.
Sulphur-reducing bacteria could become a problem if the substrate becomes
completely anoxic. But most sulpur-reducing bacteria are anoxic. The idea of
using a live gravel bed in a garden pond must take into considerations all of
the needs of the bateria that will live there. De-nitrifying bacteria are
anoxic, while ammonia reducing and nitrite-reducing bacteria are aerobic. The
idea is to get all three types growing in the same substrate. So can we expect
these three bacteria to live viably together? The answer is yes, IF oxygentated
water is induced to flow just above the gravel (parallel to it), which will
induce flow/exchange within the gravel, but at a low rate. I suspect that my
hogs (fish) will also root around in it enough looking for food that it will get
enough oxygenation. But I plan to come up with a way to create the current flow
a few inches above the gravel. I already have a very thin layer of gravel on
the bottom (I had extra gravel when I built my biofilter, and I wanted to add a
little color to the bottom of the pond), and they do root around in what I
already have there. But I will certainly take your advice at heart before I
make any final decisions. Thanks for the advice. Oh, and after reading that
article, and your advice, I will probably lose the plenum and just build the
substrate right on the bottom. Here is the link to the site I found:

http://www.athiel.com/lib/lg-fw.html

Here is another one about gravel filtration (as opposed to undergravel
filtration):

http://www.athiel.com/lib/ugfilterarticle.htm

Just read the part about gravel filtration.


I can't find the failed Jaubert attempt right off, but here's some on
similar denitrification attempts - not formal, and nobody as famous as
Thiel.

http://www.thekrib.com/Filters/plenum.html has an article on the
shortcomings of Jaubert's original idea in FW.

http://www.thekrib.com/Chemistry/nitrate.html has my own account of
trying to use a commercial denitrator called a Nitrex box. It was a
flat, black box with a nutrient mix for denitrifying bacteria that was
supposed to prevent the growth of sulfur-reducing bacteria. There were
slots for convective circulation and you buried it in the gravel to form
something like a plenum. I got nice denitrification for a while and
then the typical H2S crash and burn.

http://www.thekrib.com/Filters/denitrator.html has George Booth's DIY
coil denitrator design. Similar to my experience, after a few months of
successful operation, the coil started pumping H2S into the tank and
killing fish. George Booth is a gifted plant tank aquarist, and if
anyone could have pulled off denitrification it would be him.

I was reading rec.aquaria avidly then and nobody managed a successful
denitrator design in FW other than bog filters or algae scrubbers.

However, Thiel's live gravel article is very interesting. It's actually
quite easy to run a planted aquarium with only water movement and
minimal filtration - the so-called Dutch Aquarium. The plants and
gravel provide plenty of surface area for filtration. Malaysian trumpet
snails (alas, tropicals) provide substrate turnover, with a loach
keeping the population from getting out of hand, and the plant roots
prevent anaerobic zones from developing.

Doing this in a pond seems possible if your fish...er hogs stir the
gravel and circulation over the gravel bed is good. I wonder if there
is a coldwater snail that would burrow in the gravel to help things stay
aerobic? I'm sure you'll get plenty of healthy nitrification in the
least. I hope it works out with some denitrification as well.

--
__ Elaine T __
__' http://eethomp.com/fish.html '__

"Elaine T" wrote in message
. com...
George wrote:
"Elaine T" wrote in message
om...

George wrote:

"Sean Dinh" wrote in message
...


TT and nitrate reduction...
http://tinyurl.com/4hlhx


10 ppm is not acceptable in reef aquariums, and I strongly suspect it does
little good in large freshwater systems (such as garden ponds) with
no/inadequate plants to remove it. Hence, the algae blooms. In a sand bed
that uses a Jaubert plenum, a porous plenum is constructed beneath the bed
with a void space below the bed that is filled with water, anaerobic
bacteria form in the bottom depths of the substrate and in the water below.
As anaerobic bacteria cultivate, they remove nitrates. Anaerobic action
produces a fair amount of heat. The heat warms the water layer below the
gravel. The warmer water flows upwards, displacing cooler water above the
gravel. This action moves water through the plenum at very slow rates. The
slow movement of water through the gravel helps to prevent dangerous
hydrogen-sulfide gases from forming in the plenum. The deep gravel bed also
provides a home for burrowing motile invertebrates which feed on solid
organic mulm and detritus. The idea here is to move away from systems that
required heavy maintenance to prevent nitraqtes from getting too high.
Trickle filters work great in removing nitrogen compounds over a limited
time period before they must be maintained (i.e., cleaning pre-filters,
etc). Sand beds with a Jaubert plenum usually never have to be cleaned
because, if it is properly constructed, there is no build up.

http://www.practicalfishkeeping.co.u...?article_id=21

Jaubert plenums have been tried in large FW planted tanks shortly after they
became popular in sal****er. It is much harder to get a population of
denitrifying bacteria in FW that does not include sulfur reducing bacteria
and generally attempts at denitrification in FW crash and burn. Sulfur
reducing bacteria establish in the plenum, poison the water, and fish start
showing all sorts of bizarre diseases in what otherwise seems to be a healthy
system.

--
__ Elaine T __
__' http://eethomp.com/fish.html '__


Do you have a link to any papers on this? I found a web site this evening
that describes the set up and it seems to suggest that it works very well, at
least in freshwater aquariums. It also recommended to use 2-3 mm diameter
gravel instead of sand. Since we are talking about a lot more water, I am
considering using even larger gravel (probably something slightly smaller
than peah gravel). I've also read elsewhere that fears of crashing and
burning are unfounded if it is done properly. Of course, like any
experiment, I'll have to monitor it. Sulphur-reducing bacteria could become a
problem if the substrate becomes completely anoxic. But most sulpur-reducing
bacteria are anoxic. The idea of using a live gravel bed in a garden pond
must take into considerations all of the needs of the bateria that will live
there. De-nitrifying bacteria are anoxic, while ammonia reducing and
nitrite-reducing bacteria are aerobic. The idea is to get all three types
growing in the same substrate. So can we expect these three bacteria to live
viably together? The answer is yes, IF oxygentated water is induced to flow
just above the gravel (parallel to it), which will induce flow/exchange
within the gravel, but at a low rate. I suspect that my hogs (fish) will
also root around in it enough looking for food that it will get enough
oxygenation. But I plan to come up with a way to create the current flow a
few inches above the gravel. I already have a very thin layer of gravel on
the bottom (I had extra gravel when I built my biofilter, and I wanted to add
a little color to the bottom of the pond), and they do root around in what I
already have there. But I will certainly take your advice at heart before I
make any final decisions. Thanks for the advice. Oh, and after reading that
article, and your advice, I will probably lose the plenum and just build the
substrate right on the bottom. Here is the link to the site I found:

http://www.athiel.com/lib/lg-fw.html

Here is another one about gravel filtration (as opposed to undergravel
filtration):

http://www.athiel.com/lib/ugfilterarticle.htm

Just read the part about gravel filtration.
I can't find the failed Jaubert attempt right off, but here's some on similar
denitrification attempts - not formal, and nobody as famous as Thiel.

http://www.thekrib.com/Filters/plenum.html has an article on the shortcomings
of Jaubert's original idea in FW.

http://www.thekrib.com/Chemistry/nitrate.html has my own account of trying to
use a commercial denitrator called a Nitrex box. It was a flat, black box
with a nutrient mix for denitrifying bacteria that was supposed to prevent the
growth of sulfur-reducing bacteria. There were slots for convective
circulation and you buried it in the gravel to form something like a plenum.
I got nice denitrification for a while and then the typical H2S crash and
burn.

http://www.thekrib.com/Filters/denitrator.html has George Booth's DIY coil
denitrator design. Similar to my experience, after a few months of successful
operation, the coil started pumping H2S into the tank and killing fish.
George Booth is a gifted plant tank aquarist, and if anyone could have pulled
off denitrification it would be him.

I was reading rec.aquaria avidly then and nobody managed a successful
denitrator design in FW other than bog filters or algae scrubbers.

However, Thiel's live gravel article is very interesting. It's actually quite
easy to run a planted aquarium with only water movement and minimal
filtration - the so-called Dutch Aquarium. The plants and gravel provide
plenty of surface area for filtration. Malaysian trumpet snails (alas,
tropicals) provide substrate turnover, with a loach keeping the population
from getting out of hand, and the plant roots prevent anaerobic zones from
developing.

Doing this in a pond seems possible if your fish...er hogs stir the gravel and
circulation over the gravel bed is good. I wonder if there is a coldwater
snail that would burrow in the gravel to help things stay aerobic? I'm sure
you'll get plenty of healthy nitrification in the least. I hope it works out
with some denitrification as well.

--
__ Elaine T __
__' http://eethomp.com/fish.html '__

I am looking into what critters I can expect that might populated it
"naturally", and what I can introduce. I don't plan to plant any plants in the
substrate (it will be 45" below the water surface, at any rate).

"~ jan JJsPond.us" wrote in message
...
On Fri, 18 Mar 2005 17:34:15 GMT, (~Roy~) wrote:

Why does your pond spike so high in PH..........

I have cement blocks around the edge, last year was the worst and they
were
5 years old by that time, acid washed many times too. Don't know what the
deal was. Lots of baking soda and water changes took care of it. ~ jan

Cement blocks like pavers or cinder blocks? I would have assumed that
anything underwater would have sealed over and anything above would have
aged sufficiently. Maybe the acid washing is keeping the blocks porous and
the leeching continues.

Cement blocks like pavers or cinder blocks?

Definitely not cinder (I don't think).... more like cement block, but they
have more holes, decorative? You can see them at my website by clicking on
*Lily Pond Photos*

I would have assumed that
anything underwater would have sealed over and anything above would have
aged sufficiently. Maybe the acid washing is keeping the blocks porous and
the leeching continues.

Could be. I quit putting acid in, added 4 lbs. of baking soda and then did
4-6 water changes of 20-25% over 10 days (this was recommended by the
experts on the KHA board) it worked. Plants were happy after that. Frogs
never were bothered, amazingly. ~ jan

http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
To e-mail see website

"~ jan JJsPond.us" wrote in message
...
Cement blocks like pavers or cinder blocks?

Definitely not cinder (I don't think).... more like cement block, but they
have more holes, decorative? You can see them at my website by clicking on
*Lily Pond Photos*

I've looked at your site before, but had forgotten the Lilly Ponds. Very
attractive, but I see how they might continue to leach with all the
decorative area. But after 5 years, I would think the concrete would have
aged enough.

I would have assumed that
anything underwater would have sealed over and anything above would have
aged sufficiently. Maybe the acid washing is keeping the blocks porous
and
the leeching continues.

Could be. I quit putting acid in, added 4 lbs. of baking soda and then did
4-6 water changes of 20-25% over 10 days (this was recommended by the
experts on the KHA board) it worked. Plants were happy after that. Frogs
never were bothered, amazingly. ~ jan

Oh, the acid went in the water. Still, isn't acid etching what one does
to open the pores of concrete for adhesion of various coatings? But, you
obviously know what you're doing and how to correct the problem if it
continues.

http://users.owt.com/jjspond/

Could be. I quit putting acid in, added 4 lbs. of baking soda and then did
4-6 water changes of 20-25% over 10 days (this was recommended by the
experts on the KHA board) it worked. Plants were happy after that. Frogs
never were bothered, amazingly. ~ jan

Oh, the acid went in the water. Still, isn't acid etching what one does
to open the pores of concrete for adhesion of various coatings? But, you
obviously know what you're doing and how to correct the problem if it
continues.

I can only hope (I know what I'm doing) some days it's definitely
questionable. ;o) ~ jan

~Power to the Porg, Flow On!~