"blank" wrote in message ...
Thanks to all that replied. I really dont want to go down the CO2 track
unless all else fails; it sounds like more cost and effort than I want to
devote to the fish. But Im absolutely determined to have excellent plants.
I work with plants at a fairly sophisticated level, and have a great garden,
so my ego insists I can master aquatic plants.

I guess I'd better find a good electrician who understands aquariums (now
theres a project that might take some doing) and see about re-wiring for
compacts fluros. I like that option.

But Im still in the dark about duplarit. Ah well.

There is nothing in the dark about it.
You don't need it given your goals.
If gardening is your goal, you need to realize that CO2 is very much a
fertilizer like NPK.

Carbon is roughly 40%+ the biomass in a plant. Terrestrial plants have
little problem accessing the CO2 in air. Aquatic plants need roughly
30ppm to fully saturate their CO2 needs at their max light levels.

So why add something that will cost you 100$, when it's only less than
0.06% of the issue like Fe?

You would get much more use out of the CO2, even at low light. That
would maximize the light use efficiency if you do not want to use more
lighting.
Retro fitting could also be done with existing lighting.

But if CO2 is out of the question you need to try a non CO2 approach.
Do NOT try and do a mix of CO2 and non CO2 approaches!

Both methods work, but for different reasons.

Non CO2:
Some folks use sand and soil, some use sand peat and soil, some use
Onyx and peat some use Flourite and peat.
I prefer the Onyx and sand mix over the long term.

The substrates are roughly 10cm or so deep. The bottom is 2 cm of
ground peat moss that has been wetted and soak and a day or two. If
you opt for the soil method, soak this for 2-3 weeks. This will leech
out and nitrify the NH4 to NO3. NH4 is the enemy and will cause algae
if it's rate of production or addition is too great for the tank.

Use easy to grow plants and plant heavily.
This is the same in any tank.

Add alagae eaters.

Add 10-25% of the surface with floating plants like water sprite.
These have no CO2 issues and can soak up any shock loads.

Do not do any water changes except topping the tank off for
evaporation except when you have to go in a do a good cleaning/pruning
which should be in the 3-6 month range.

The fertilizer for the plants= fish food and waste.
You should add about 1/4 teaspoon of SeaChem Equilibrium once a week
or two.
It has a few nutrients that will help.

So regular fish feeding is a key to this method.

When you add CO2 and or/more light, this remineralization process
cannot keep up with the rate of plant growth and we need to add CO2,
more light, KNO3, PO4 etc to keep the plants actively growing.

These inorganic sources might not jive with your natural gardening
methods and approaches. But hydroponics is essentially the terrestrial
equivalent, but we cannot have NH4 because of algae which is not an
issue in terrestrial systems, but we don't have fugal or insect
herbivores pest either. There are few aquatic plant diseases,
actually, I've never seen one.

The other thing to consider when getting CO2 etc. It's cheap once you
have it. KNO3, KH2PO4, a kg or so will last for many years and only
cost a few$.
Plant cuttings can be sold to the LFS's and friends etc each week or
two with CO2.

So these things pay for themselves rapidly. Plants are much easier to
raise and ship than fish. They also grow much faster.

So if you like gardening and like it to be active and have less
patience, CO2 wikll agree with you.Non CO2 tanks take more patience
and time. Some plants are tougher without CO2 also and will need
phased in slowly after the other easy to grow plants have been well
established.
It might tank 2 years to get a tank where you could have it in 2
months with CO2.

Regards,
Tom Barr