Building an Algae Farm - musings of a nutter.

[Bill Stock]

A few months back (couldn't find the thread) NetMax was talking about the
Algae growing inside filter tubing. He surmised that you could take this to
the extreme and have enough coiled tubing exposed to light to put a serious
dent in your Nitrates. After my indoor pond experiment with it's very large
biofilter and no mechanical filter, I saw that I could keep Nitrates at
zero. I do see small Ammonia spikes just before lights on, as the plants are
doing more to remove Ammonia/Nitrates than the limited nitrifying bacteria.

My aquarium goldfish have always had Nitrate problems off and on. Even with
light feeding and religious water changes, the Nitrates still creep up now
and then. I've tried various plants with them, but they either get eaten or
torn up, which just adds to the detritus in the filter. I've thought about
filling a garbage can with plants and using this as a biofilter. But it
would not be big enough to make much difference in the Nitrates, unless it
was huge.

So getting back to NM's Algae idea. I was reading on the Krib about the
nutrient uptake of various plants. Not surprisingly Water Hyacinth came out
on top at 1278 mg of Nitrates removed per square meter day. This is very
good, but they are floating plants and take up a lot of space. But Algae
consumes between 300 and 1200 mg of Nitrates per square meter per day. So if
I had 15 square meters of Algae sucking power, I could remove up to 15
grams of Nitrates per day!

The easiest design I could come up with for this was to use an old aquarium,
say 24*16*16, about 25 gallons. If I were to hang 47 glass slides vertically
(or plastic film) at half inch intervals, I would have 16 square meters of
Algae. I can see several problems with this, a) light
distribution/penetration b) Smell c) Bacteria? d) Algae die off?

Apart from the fact that you think it's an insane idea. Any better design
suggestions?

Thanks.

[Elaine T]

Bill Stock wrote:
> A few months back (couldn't find the thread) NetMax was talking about the
> Algae growing inside filter tubing. He surmised that you could take this to
> the extreme and have enough coiled tubing exposed to light to put a serious
> dent in your Nitrates. After my indoor pond experiment with it's very large
> biofilter and no mechanical filter, I saw that I could keep Nitrates at
> zero. I do see small Ammonia spikes just before lights on, as the plants are
> doing more to remove Ammonia/Nitrates than the limited nitrifying bacteria.
>
> My aquarium goldfish have always had Nitrate problems off and on. Even with
> light feeding and religious water changes, the Nitrates still creep up now
> and then. I've tried various plants with them, but they either get eaten or
> torn up, which just adds to the detritus in the filter. I've thought about
> filling a garbage can with plants and using this as a biofilter. But it
> would not be big enough to make much difference in the Nitrates, unless it
> was huge.
>
> So getting back to NM's Algae idea. I was reading on the Krib about the
> nutrient uptake of various plants. Not surprisingly Water Hyacinth came out
> on top at 1278 mg of Nitrates removed per square meter day. This is very
> good, but they are floating plants and take up a lot of space. But Algae
> consumes between 300 and 1200 mg of Nitrates per square meter per day. So if
> I had 15 square meters of Algae sucking power, I could remove up to 15
> grams of Nitrates per day!
>
> The easiest design I could come up with for this was to use an old aquarium,
> say 24*16*16, about 25 gallons. If I were to hang 47 glass slides vertically
> (or plastic film) at half inch intervals, I would have 16 square meters of
> Algae. I can see several problems with this, a) light
> distribution/penetration b) Smell c) Bacteria? d) Algae die off?
>
> Apart from the fact that you think it's an insane idea. Any better design
> suggestions?
>
> Thanks.
>

The idea of algae as a nitrogen sponge has been worked out. It's used
mostly in sal****er where very few higher plants can grow. Marine
aquarists use algal turf scrubbers with mixed results. Filamentous
algae is grown on plastic screening (similar to window screen) in a
wide, flat container under bright lights. The screening is scraped or
part of it changed fairly frequently. Google on "algal turf scrubber"
and you should find more info.

Really, a sump full of water hyacinth should do the trick unless you're
talking about a tank full of koi. It needs a lot of light, but other
than that it's undemanding and would probably be less work than building
and running a scrubber.

http://www.hdltd.com/index.html also sells a bacillus mix that
supposedly reduces nitrate in both salt and freshwater. I tried it and
got the rapid cycle they advertise, but my tanks have so many plants
that I don't know what's actually dropping the nitrate.

--
Elaine T __
http://eethomp.com/fish.html <'__><
rec.aquaria.* FAQ http://faq.thekrib.com

[Bill Stock]

"Elaine T" > wrote in message
. com...
> Bill Stock wrote:
>> A few months back (couldn't find the thread) NetMax was talking about the
>> Algae growing inside filter tubing. He surmised that you could take this
>> to the extreme and have enough coiled tubing exposed to light to put a
>> serious dent in your Nitrates. After my indoor pond experiment with it's
>> very large biofilter and no mechanical filter, I saw that I could keep
>> Nitrates at zero. I do see small Ammonia spikes just before lights on, as
>> the plants are doing more to remove Ammonia/Nitrates than the limited
>> nitrifying bacteria.
>>
>> My aquarium goldfish have always had Nitrate problems off and on. Even
>> with light feeding and religious water changes, the Nitrates still creep
>> up now and then. I've tried various plants with them, but they either get
>> eaten or torn up, which just adds to the detritus in the filter. I've
>> thought about filling a garbage can with plants and using this as a
>> biofilter. But it would not be big enough to make much difference in the
>> Nitrates, unless it was huge.
>>
>> So getting back to NM's Algae idea. I was reading on the Krib about the
>> nutrient uptake of various plants. Not surprisingly Water Hyacinth came
>> out on top at 1278 mg of Nitrates removed per square meter day. This is
>> very good, but they are floating plants and take up a lot of space. But
>> Algae consumes between 300 and 1200 mg of Nitrates per square meter per
>> day. So if I had 15 square meters of Algae sucking power, I could remove
>> up to 15 grams of Nitrates per day!
>>
>> The easiest design I could come up with for this was to use an old
>> aquarium, say 24*16*16, about 25 gallons. If I were to hang 47 glass
>> slides vertically (or plastic film) at half inch intervals, I would have
>> 16 square meters of Algae. I can see several problems with this, a) light
>> distribution/penetration b) Smell c) Bacteria? d) Algae die off?
>>
>> Apart from the fact that you think it's an insane idea. Any better design
>> suggestions?
>>
>> Thanks.
>>
>
> The idea of algae as a nitrogen sponge has been worked out. It's used
> mostly in sal****er where very few higher plants can grow. Marine
> aquarists use algal turf scrubbers with mixed results. Filamentous algae
> is grown on plastic screening (similar to window screen) in a wide, flat
> container under bright lights. The screening is scraped or part of it
> changed fairly frequently. Google on "algal turf scrubber" and you should
> find more info.

Damn, so much for an original idea.

> Really, a sump full of water hyacinth should do the trick unless you're
> talking about a tank full of koi. It needs a lot of light, but other than
> that it's undemanding and would probably be less work than building and
> running a scrubber.

Thanks Elaine, but I just can't see a bucket (sump) of WH doing much for a
75 gallon tank at 40 ppm Nitrates. Even if I could get a metre of WH, that
would only reduce the Nitrates by 1 gram per day. But at 40 ppm I would have
10 grams or so.


> http://www.hdltd.com/index.html also sells a bacillus mix that supposedly
> reduces nitrate in both salt and freshwater. I tried it and got the rapid
> cycle they advertise, but my tanks have so many plants that I don't know
> what's actually dropping the nitrate.
>
> --
> Elaine T __
> http://eethomp.com/fish.html <'__><
> rec.aquaria.* FAQ http://faq.thekrib.com

[NetMax]

"Bill Stock" > wrote in message
...
>
> "Elaine T" > wrote in message
> . com...
>> Bill Stock wrote:
>>> A few months back (couldn't find the thread) NetMax was talking about
>>> the Algae growing inside filter tubing. He surmised that you could
>>> take this to the extreme and have enough coiled tubing exposed to
>>> light to put a serious dent in your Nitrates. After my indoor pond
>>> experiment with it's very large biofilter and no mechanical filter, I
>>> saw that I could keep Nitrates at zero. I do see small Ammonia spikes
>>> just before lights on, as the plants are doing more to remove
>>> Ammonia/Nitrates than the limited nitrifying bacteria.
>>>
>>> My aquarium goldfish have always had Nitrate problems off and on.
>>> Even with light feeding and religious water changes, the Nitrates
>>> still creep up now and then. I've tried various plants with them, but
>>> they either get eaten or torn up, which just adds to the detritus in
>>> the filter. I've thought about filling a garbage can with plants and
>>> using this as a biofilter. But it would not be big enough to make
>>> much difference in the Nitrates, unless it was huge.
>>>
>>> So getting back to NM's Algae idea. I was reading on the Krib about
>>> the nutrient uptake of various plants. Not surprisingly Water
>>> Hyacinth came out on top at 1278 mg of Nitrates removed per square
>>> meter day. This is very good, but they are floating plants and take
>>> up a lot of space. But Algae consumes between 300 and 1200 mg of
>>> Nitrates per square meter per day. So if I had 15 square meters of
>>> Algae sucking power, I could remove up to 15 grams of Nitrates per
>>> day!
>>>
>>> The easiest design I could come up with for this was to use an old
>>> aquarium, say 24*16*16, about 25 gallons. If I were to hang 47 glass
>>> slides vertically (or plastic film) at half inch intervals, I would
>>> have 16 square meters of Algae. I can see several problems with this,
>>> a) light distribution/penetration b) Smell c) Bacteria? d) Algae die
>>> off?
>>>
>>> Apart from the fact that you think it's an insane idea. Any better
>>> design suggestions?
>>>
>>> Thanks.


My idea at one time was to use plastic screens sliding on brackets
siliconed to the sides of a long 32g tank. Then having flourescent
lights on the sides, top & bottom, and the tank inline with the return to
the main tank (no pumps to get clogged up). Have more screens than
needed and periodically clean a few as required. Screens should not be
full height. Leave an inch clearance, and every 2nd screen sits at the
bottom, every other screen touches the surface (the water slides up and
down, and through the screen, maximizing surface efficiency.

I've never assembled it, so I don't know if it presents any special
challenges, but I don't forsee any.
--
www.NetMax.tk

>> The idea of algae as a nitrogen sponge has been worked out. It's used
>> mostly in sal****er where very few higher plants can grow. Marine
>> aquarists use algal turf scrubbers with mixed results. Filamentous
>> algae is grown on plastic screening (similar to window screen) in a
>> wide, flat container under bright lights. The screening is scraped or
>> part of it changed fairly frequently. Google on "algal turf scrubber"
>> and you should find more info.
>
> Damn, so much for an original idea.
>
>> Really, a sump full of water hyacinth should do the trick unless
>> you're talking about a tank full of koi. It needs a lot of light, but
>> other than that it's undemanding and would probably be less work than
>> building and running a scrubber.
>
> Thanks Elaine, but I just can't see a bucket (sump) of WH doing much
> for a 75 gallon tank at 40 ppm Nitrates. Even if I could get a metre of
> WH, that would only reduce the Nitrates by 1 gram per day. But at 40
> ppm I would have 10 grams or so.
>
>
>> http://www.hdltd.com/index.html also sells a bacillus mix that
>> supposedly reduces nitrate in both salt and freshwater. I tried it
>> and got the rapid cycle they advertise, but my tanks have so many
>> plants that I don't know what's actually dropping the nitrate.
>>
>> --
>> Elaine T __
>> http://eethomp.com/fish.html <'__><
>> rec.aquaria.* FAQ http://faq.thekrib.com
>
>

[Elaine T]

Bill Stock wrote:
> "Elaine T" > wrote in message
> . com...
>
>>Bill Stock wrote:
>>
>>>A few months back (couldn't find the thread) NetMax was talking about the
>>>Algae growing inside filter tubing. He surmised that you could take this
>>>to the extreme and have enough coiled tubing exposed to light to put a
>>>serious dent in your Nitrates. After my indoor pond experiment with it's
>>>very large biofilter and no mechanical filter, I saw that I could keep
>>>Nitrates at zero. I do see small Ammonia spikes just before lights on, as
>>>the plants are doing more to remove Ammonia/Nitrates than the limited
>>>nitrifying bacteria.
>>>
>>>My aquarium goldfish have always had Nitrate problems off and on. Even
>>>with light feeding and religious water changes, the Nitrates still creep
>>>up now and then. I've tried various plants with them, but they either get
>>>eaten or torn up, which just adds to the detritus in the filter. I've
>>>thought about filling a garbage can with plants and using this as a
>>>biofilter. But it would not be big enough to make much difference in the
>>>Nitrates, unless it was huge.
>>>
>>>So getting back to NM's Algae idea. I was reading on the Krib about the
>>>nutrient uptake of various plants. Not surprisingly Water Hyacinth came
>>>out on top at 1278 mg of Nitrates removed per square meter day. This is
>>>very good, but they are floating plants and take up a lot of space. But
>>>Algae consumes between 300 and 1200 mg of Nitrates per square meter per
>>>day. So if I had 15 square meters of Algae sucking power, I could remove
>>>up to 15 grams of Nitrates per day!
>>>
>>>The easiest design I could come up with for this was to use an old
>>>aquarium, say 24*16*16, about 25 gallons. If I were to hang 47 glass
>>>slides vertically (or plastic film) at half inch intervals, I would have
>>>16 square meters of Algae. I can see several problems with this, a) light
>>>distribution/penetration b) Smell c) Bacteria? d) Algae die off?
>>>
>>>Apart from the fact that you think it's an insane idea. Any better design
>>>suggestions?
>>>
>>>Thanks.
>>>
>>
>>The idea of algae as a nitrogen sponge has been worked out. It's used
>>mostly in sal****er where very few higher plants can grow. Marine
>>aquarists use algal turf scrubbers with mixed results. Filamentous algae
>>is grown on plastic screening (similar to window screen) in a wide, flat
>>container under bright lights. The screening is scraped or part of it
>>changed fairly frequently. Google on "algal turf scrubber" and you should
>>find more info.
>
>
> Damn, so much for an original idea.
>
>
>>Really, a sump full of water hyacinth should do the trick unless you're
>>talking about a tank full of koi. It needs a lot of light, but other than
>>that it's undemanding and would probably be less work than building and
>>running a scrubber.
>
>
> Thanks Elaine, but I just can't see a bucket (sump) of WH doing much for a
> 75 gallon tank at 40 ppm Nitrates. Even if I could get a metre of WH, that
> would only reduce the Nitrates by 1 gram per day. But at 40 ppm I would have
> 10 grams or so.

This summer, WH covering 50% of my pond surface (three half whiskey
barrels) in direct sunlight used all the nitrates from two 3" goldfish,
two greedy 4" koi, a handful of white clouds and gambusia, plus 15 ppm
of extra nitrates a week, minimum. I know that because that's how much
fertilizer I had to add weekly to keep the silly stuff green and not
brownish-red. I was pulling the stuff out by the handfulls and selling
it to fish stores, giving it away, and finally throwing it away. It's
worse than zucchini! The volume in the pond is about 75 gallons.

I don't know the conditions for the measurements you cited. In my
hands, outdoors in full morning sun, WH is an impressive nitrate sink.
YMMV indoors in a sump, and algae will certainly work well too.

--
Elaine T __
http://eethomp.com/fish.html <'__><
rec.aquaria.* FAQ http://faq.thekrib.com

[A Man]

I use duckweed to get the nitrates out. But once you have duckweed it's
difficult to remove every last leaf. When surface area covered >=75% then I
scoop out enough so coverage is down to 25%. I generally have to do this
about once every 6-7 weeks.

No company will sell duckweed because it's so invasive, but private people
might. Try aquabid.com.

--
Sig: Say no to fixed width HTML tables. They look terrible in most browsers.

[Elaine T]

A Man wrote:
> I use duckweed to get the nitrates out. But once you have duckweed it's
> difficult to remove every last leaf. When surface area covered >=75% then I
> scoop out enough so coverage is down to 25%. I generally have to do this
> about once every 6-7 weeks.
>
> No company will sell duckweed because it's so invasive, but private people
> might. Try aquabid.com.
>
That's a great idea. Plus some goldfish eat duckweed so they may keep
it under control. My big shubunkin eats all of it that I put in his barrel.

--
Elaine T __
http://eethomp.com/fish.html <'__><
rec.aquaria.* FAQ http://faq.thekrib.com