Strange water chemistry in my large tank

[D. J]

Hello,

I have built myself a 1000G tank (8'x6'x3'), it now has 4 full grown fish
that each is a foot long, and a dozen of juvenile cichlids from 2" to 4", it
has been in service for 6 weeks till now, I have a 70 Gallon home made
Wet/dry filter which is driven by a 2200 GPH pump, it has open cell foam
pads as media, it also have a in tank filter that is driven by a 700GPH
pump, it has very small amount of gravel at the bottom which is from my old
tanks, I also used some of the mature media from my old tank's filter so it
cycled in just 2 weeks at first.

The problem I am having now is after all the fish were put in, I have been
measuring a Ammonia level between 0.25-0.5ppm for 4 weeks, it never passes 1
ppm and never drops below 0.25 ppm either. I have done 10% water change more
than 10 times in the pass 4 weeks, it had very little effect to the Ammonia
level. All my fish are eating pretty well, except just a large full grown
Red Devil is showing some stress, but I guess it's still acclimating.

The strange thing is that I get absolute 0 Nitrite ever since the end of 2nd
week, I questioned my Ammonia and Nitriate test kits, so they were verified
with water from other tanks, they all showed 0 Ammonia and Nitrite, so can
anybody explain what is going on in my tank?

Thanks.

D. J

[[email protected]]

Sorry for being unhelpful, but I'd like to see pictures of your nice
tank.

[Margolis]

what is your nitrate level? I am going to hazard a guess and say that the
tank is not cycled yet. Just because you added some old media is no
guarantee of quick cycling. It usually does the trick though. But damn,
that's a huge tank. One thing is your filtration, it just isn't enough for
a tank that size, in my opinion. I have a friend with a 250 gallon tank with
that much filtration. ;o0 You 'may' not be turning the tank over enough. On
a 1000 gallon tank I would be pumping more like 5000gph through the wet/dry.
Are the inlets and outlets for the filter at opposite ends of the tank to
get good circulation?


--

Margolis
http://web.archive.org/web/20030215212142/http://www.agqx.org/faqs/AGQ2FAQ.htm
http://www.unrealtower.org/faq

[George Pontis]

In article >, says...
> Hello,
>
> I have built myself a 1000G tank (8'x6'x3'), it now has 4 full grown fish
> that each is a foot long, and a dozen of juvenile cichlids from 2" to 4", it
> has been in service for 6 weeks till now, I have a 70 Gallon home made
> Wet/dry filter which is driven by a 2200 GPH pump, it has open cell foam
> pads as media, it also have a in tank filter that is driven by a 700GPH
> pump, it has very small amount of gravel at the bottom which is from my old
> tanks, I also used some of the mature media from my old tank's filter so it
> cycled in just 2 weeks at first.

Impressive, did you also build a quick water change system ? 10%-20% of 1000
gallons, that would be taxing a bucket brigade.

> The problem I am having now is after all the fish were put in, I have been
> measuring a Ammonia level between 0.25-0.5ppm for 4 weeks, it never passes 1
> ppm and never drops below 0.25 ppm either. I have done 10% water change more
> than 10 times in the pass 4 weeks, it had very little effect to the Ammonia
> level. All my fish are eating pretty well, except just a large full grown
> Red Devil is showing some stress, but I guess it's still acclimating.

A few guesses: Is the biological filter area really as large as you think it is ?
Or perhaps the filter is not providing as much oxygen as the bacterial could use,
reducing their metabolic rate. Possibly there is something in the foam that you
have chosen that is counterproductive. For example, some rigid foams outgassed
formaldehyde, perhaps there is a compound in your foam that is biologically active
?

[NetMax]

"D. J" > wrote in message
...
> Hello,
>
> I have built myself a 1000G tank (8'x6'x3'), it now has 4 full grown
> fish
> that each is a foot long, and a dozen of juvenile cichlids from 2" to
> 4", it
> has been in service for 6 weeks till now, I have a 70 Gallon home made
> Wet/dry filter which is driven by a 2200 GPH pump, it has open cell
> foam
> pads as media, it also have a in tank filter that is driven by a 700GPH
> pump, it has very small amount of gravel at the bottom which is from my
> old
> tanks, I also used some of the mature media from my old tank's filter
> so it
> cycled in just 2 weeks at first.
>
> The problem I am having now is after all the fish were put in, I have
> been
> measuring a Ammonia level between 0.25-0.5ppm for 4 weeks, it never
> passes 1
> ppm and never drops below 0.25 ppm either. I have done 10% water change
> more
> than 10 times in the pass 4 weeks, it had very little effect to the
> Ammonia
> level. All my fish are eating pretty well, except just a large full
> grown
> Red Devil is showing some stress, but I guess it's still acclimating.
>
> The strange thing is that I get absolute 0 Nitrite ever since the end
> of 2nd
> week, I questioned my Ammonia and Nitriate test kits, so they were
> verified
> with water from other tanks, they all showed 0 Ammonia and Nitrite, so
> can
> anybody explain what is going on in my tank?
>
> Thanks.
>
> D. J


My guess, is that you don't have enough biological activity (ie: suitable
surface) established, or are not exchanging the water quickly enough.
Normally the ammonia-nitrite-nitrate consumption is balanced, but when it
goes out of balance, you hear about ammonia, not nitrite. I suspect that
the nitrite producing bacteria might be slower to establish, but less
difficult to maintain. Is all of the sponge's surface being kept wet?
Is there sufficient flow through the tank? Are the feeding one single
large portion or spread out in smaller portions. Is the ammonia level
lower in the AM before the first feeding? Is the pH higher than 6.5?
--
www.NetMax.tk

[D. J]

"Margolis" > wrote in message
...
> what is your nitrate level? I am going to hazard a guess and say that the
> tank is not cycled yet. Just because you added some old media is no
> guarantee of quick cycling. It usually does the trick though. But damn,
> that's a huge tank. One thing is your filtration, it just isn't enough
for
> a tank that size, in my opinion. I have a friend with a 250 gallon tank
with
> that much filtration. ;o0 You 'may' not be turning the tank over enough.
On
> a 1000 gallon tank I would be pumping more like 5000gph through the
wet/dry.
> Are the inlets and outlets for the filter at opposite ends of the tank to
> get good circulation?

I haven't measured nitrate level, but I can see algae growing on the rocks,
maybe this is the indication that nitrate is showing up? I will get a
nitrate kit and try it.

I too feel the filtration is on the low side for the size of the tank, but
for now my fish load is not high either, the amount of food I dump into the
tank is even less than what I dump into my 180G. Yes, the inlets and outlets
are opposite.

D. J

[D. J]

> wrote in message
oups.com...
> Sorry for being unhelpful, but I'd like to see pictures of your nice
> tank.
>
It is not a conventional tank, it is very large plywood tank lined with pond
liner, it has a relatively small window (48"X24"), so it doesn't look as
impressive as it sounds.

See below link for a picture, it's impossible to take a good one of it in
the basement, so most of fish can't be seen from the picture
http://members.rogers.com/dongxun1/images/0502220031.JPG

D. J

[D. J]

"George Pontis" > wrote in message
...
> In article >,
says...
> > Hello,
> >
> > I have built myself a 1000G tank (8'x6'x3'), it now has 4 full grown
fish
> > that each is a foot long, and a dozen of juvenile cichlids from 2" to
4", it
> > has been in service for 6 weeks till now, I have a 70 Gallon home made
> > Wet/dry filter which is driven by a 2200 GPH pump, it has open cell foam
> > pads as media, it also have a in tank filter that is driven by a 700GPH
> > pump, it has very small amount of gravel at the bottom which is from my
old
> > tanks, I also used some of the mature media from my old tank's filter so
it
> > cycled in just 2 weeks at first.
>
> Impressive, did you also build a quick water change system ? 10%-20% of
1000
> gallons, that would be taxing a bucket brigade.
>
It has a floor drain, so changing water 10% of water is 10 minutes work,
doesn't even wet my hands.

> > The problem I am having now is after all the fish were put in, I have
been
> > measuring a Ammonia level between 0.25-0.5ppm for 4 weeks, it never
passes 1
> > ppm and never drops below 0.25 ppm either. I have done 10% water change
more
> > than 10 times in the pass 4 weeks, it had very little effect to the
Ammonia
> > level. All my fish are eating pretty well, except just a large full
grown
> > Red Devil is showing some stress, but I guess it's still acclimating.
>
> A few guesses: Is the biological filter area really as large as you think
it is ?
> Or perhaps the filter is not providing as much oxygen as the bacterial
could use,
> reducing their metabolic rate. Possibly there is something in the foam
that you
> have chosen that is counterproductive. For example, some rigid foams
outgassed
> formaldehyde, perhaps there is a compound in your foam that is
biologically active
> ?
Yes, the wet/dry is not fully filled with media yet, I think this is the
problem, I have only 10 Gallon media in its 70 Gallon capacity, I thought
the tank is big and fish load is not high, maybe 10 Gallon media was good
enough for now, maybe I was wrong.

The foam is the same type of foam that I used in my other tanks.

D. J

[D. J]

"NetMax" > wrote in message
. ..
> My guess, is that you don't have enough biological activity (ie: suitable
> surface) established, or are not exchanging the water quickly enough.
> Normally the ammonia-nitrite-nitrate consumption is balanced, but when it
> goes out of balance, you hear about ammonia, not nitrite. I suspect that
> the nitrite producing bacteria might be slower to establish, but less
> difficult to maintain. Is all of the sponge's surface being kept wet?
> Is there sufficient flow through the tank? Are the feeding one single
> large portion or spread out in smaller portions. Is the ammonia level
> lower in the AM before the first feeding? Is the pH higher than 6.5?
> --
> www.NetMax.tk

I have only approx. 10 Gallon sponges in wet/dry's 70 Gallon chamber, I
thought 10G media was good enough for the beginning when fish load was low,
so I put egg crates underneath the media, raised their height so they can be
submerged.
I have 2 inlets at right side of the tank near the water line, 1 outlet on
the left side bottom, water is drained from outlet then sprinkled on
wet/dry's prefilter. I feed them twice a day. YES, indeed, ammonia is lower
in the morning before the feeding, and gets worst at night, and my PH is
almost 7.5.

Any further thoughts will be appreciated.

D. J

[Margolis]

"D. J" > wrote in message
...
>
> liner, it has a relatively small window (48"X24"), so it doesn't look as
> impressive as it sounds.
>



It may not look as good as some people would like, but I am sure the fish
will be happy in it once the kinks get worked out ;o)

--

Margolis
http://web.archive.org/web/20030215212142/http://www.agqx.org/faqs/AGQ2FAQ.htm
http://www.unrealtower.org/faq

[NetMax]

"D. J" > wrote in message
...
>
> "NetMax" > wrote in message
> . ..
>> My guess, is that you don't have enough biological activity (ie:
>> suitable
>> surface) established, or are not exchanging the water quickly enough.
>> Normally the ammonia-nitrite-nitrate consumption is balanced, but when
>> it
>> goes out of balance, you hear about ammonia, not nitrite. I suspect
>> that
>> the nitrite producing bacteria might be slower to establish, but less
>> difficult to maintain. Is all of the sponge's surface being kept wet?
>> Is there sufficient flow through the tank? Are the feeding one single
>> large portion or spread out in smaller portions. Is the ammonia level
>> lower in the AM before the first feeding? Is the pH higher than 6.5?
>> --
>> www.NetMax.tk
>
> I have only approx. 10 Gallon sponges in wet/dry's 70 Gallon chamber, I
> thought 10G media was good enough for the beginning when fish load was
> low,
> so I put egg crates underneath the media, raised their height so they
> can be
> submerged.
> I have 2 inlets at right side of the tank near the water line, 1 outlet
> on
> the left side bottom, water is drained from outlet then sprinkled on
> wet/dry's prefilter. I feed them twice a day. YES, indeed, ammonia is
> lower
> in the morning before the feeding, and gets worst at night, and my PH
> is
> almost 7.5.
>
> Any further thoughts will be appreciated.
>
> D. J


Sounds like more filter media might help. Don't worry about is being
submerged. It will still act as a biological filter. It's efficiency
increases as it's closer to the air where the O2 concentration is higher,
but it's still working at the bottom of the sump tank if there is a
current flowing past.
--
www.NetMax.tk