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Alrite I Am Going To Buy Some Java Moss, Najas And Mabey Dwarf Hair Grass But I Been Hearing Thing About Giving Plants Co2. But How Do U Give Them Co2 When They Are Under Water? But Isnt A Pump Good Enough Because It Gives Air? Reply asap

Hi,
Before you purchase the Java Moss, and the Dwarf Hair Grass
you should be sure that your lighting for the tank is at
least 2 watts per gallon (total the wattages of your bulb(s)
and divide by the capacity of the tank). The flourscent
lights should be marked DAYLIGHT or SUNLIGHT, or they should
say 6700K. That will set the tank up, lighting wise, for the
plants that you mentioned. The third plant is an "easy" care
plant that also appreciates at least "medium" light (2 wpg).

As far as the CO2 is concerned, it is not really necessary
as long as you stay below 3+wpg, or you don't want to step
up the plant growth more than normal. Plants will thrive
perfectly fine without injecting CO2. They will get their
Carbon from the organics within the tank as the fish food
and fish waste decay.

The limiting factors to plant growth are light, and the
availablility of Carbon, among others. Light is the
engine that drives the process of photosynthesis, and
Carbon is the major "fuel" in the process. Light is easy.
We simply add more lights, or stronger lights. The Carbon
is more difficult. Breaking down the organics in the tank
can take quite a bit of energy for some plants, and it
also depends upon what molecules are present, and
how tightly the Carbon atom is bound to the molecule.

Water contains about 5 miligrams per liter (mg/l) normally.
This is the normal saturation, 5 mg/l. When we inject CO2,
into the tank, we can raise the CO2 saturation to quite high
levels, sometimes lethel levels for the fish. The injection
process is quite simple, we simply generate the CO2 gas and
force it through an airline into a type of airstone that
creates bunches and bunches of very, very, tiny bubbles.
As the bubbles slowly rise towards the surface, they are
absorbed by the water and the CO2 saturation of the water
increases. The longer the bubbles are in contact with the
water, the more CO2 is absorbed. The tiny bubbles are
subject to the currents within the tank and instead of
rising directly to the surface and bursting, they drift
arround for quite a while and actually very few reach the
surface and are lost. There is another way, that is to
use a Glass Diffuser (even smaller bubbles, and more
expensive) or a Reactor (a small tank with many passages
where water and the gas are mixed and circulated, and then
released into the tank).

Read the threads on this site about "Do It Yourself" (DIY)
CO2 generation ( a bottle, some yeast, some water, and some
sugar) or the "bottled" CO2 systems. Each has its
advantages and disadvantages.

By providing CO2 gas to the tank water, and increasing the
CO2 saturation, the plants now have plenty of Carbon, and
with the right light, some of them will seem to grow before
your eyes. A couple of inches a day is not unreasonable.
If you decide to try CO2 injection, you will need to know
the pH of your tank, and the Carbonate Hardness (KH) of
your tank. Once you start the injection, to determine the
CO2 saturation, you simply test the water for those two
values, and then look on a chart for where they intersect,
and that number is the saturation. Plants do best when the
CO2 saturation is between 15mg/l and 30mg/l. Saturations
over 30 can cause problems for the fish and they can start
gasping at the surface for more air (O2).

This is some more information on the CO2 injection including
the necessary charts.

{link]http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm[/href]

Hope this helps...
Frank



-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

In addition to what Frank has said.....and to underline it in a way

First look @what light you have, and or how much you're willing to upgrade to.
Once you know how much light you'll have available you can begin selecting plants. Once the plants are decided on, then you can decide if you want, and or need, CO2 injections.
Depending on the stock you may not want to have an airstone running as it will drive off the CO2 that the fish produce. If you do start suppliment CO2 with a DIY unit or some other method you'll want to minimize surface agitation.

Of my 3 planted tanks, one is kept as low light and does not need CO2, another has medium light and does not recieve C02, there is growth but not what you'd consider daily growth. The one that does recieve C02 does show growth on a daily basis, but did fine without.

^_^
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