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Re: High Light, Nutrient Diffusion and Plenum



Subject: re: High light without CO2 

Shaji,

> >> Karen, are you saying that you *need* CO2 and and trace elements to
> >> keep a tank in balance if you have high light?  
> >
> >What I'm saying is that you *need* to balance the light in the tank with
> >adequate amounts of CO2 and trace elements.  If you can do this without 
> >artificial supplementation, that's terrific... but it's a difficult 
> >balancing act that most people can't achieve.
> 
> I'll take that as a yes :-).

It most emphatically was _not_ a "yes", it was a "maybe".  I have not seen 
you tanks, so have only your word to go on.  But if you say you are growing 
high light plants I believe you.  I have seen some higher light plants come 
out of Dorothy Reimer's tanks that were beautiful, and obviously well grown. 
 She goes you one step better... she doesn't even use bright light!

From what I have seen you have to have particularly good tap water 
conditions to be able to do this.  The better (soft, close to neutral, no 
toxic chemicals) your water is, the less you have to do to grow nice plants. 
 Those of us (and there are _many_) with less optimal water conditions have 
to resort to other means.

Again, If your plants are growing well _long term_, and you are not 
experiencing algae problems, your tank _is_ in balance.  

> There are people on this list who say that low-tech tanks, period, are
> an exercise in futility. 

This is clearly nonsense. People have been growing aquatic plants for 
decades without "high tech" equipment.  

>Most newcomers to the aquatic gardening area will probably agree, at least 
>for a year or so.  

Why? I've started several new hobbyists out with low-tech planted tanks.  
They have _all_ been successful.  Heck, I started out with low tech tanks, 
and had at least moderate success with my plants with _none_ of the 
knowledge I have now, and no one to turn to for help.  We all have to start 
somewhere. 

>You seem to be saying that low-tech tanks are possible, but that you are 
>best off sticking with low light and slow-growing plants.

No.  Again, I maintain that light, CO2, trace elements, stocking levels and 
maintenance must be *IN BALANCE* to have a successful planted tank.  _THEN_, 
based on your lighting levels, you make an educated guess on what will work 
in your tank, and go from there.  Everyone will have success with some 
plants, and less (or none) with others.  If a particular plant doesn't work 
for you, move on to something else.  Once your tank is doing well, with good 
growth from a number of species, you can experiment with plants that seem 
"iffy" for your set-up.  Losing one specimen is no big deal.  Losing a whole 
tank full of plants because you disregard what we already know about plants 
and put them in unsuitable conditions, is just plain wasting money.<g>

> I think that are just too many variables in raising plants the
> low-tech way, and that experimenting to figure out what works for you
> is the only way.  You have to figure out how to complement the
> nutrients in your local water.  You have to figure out what mix of
> plants works for you.  And IMO, lighting is one of the parameters
> that you have to play with.  I don't axiomatically rule out high light
> in a low-tech tank.

Experimentation is fine as long as you start with a basic understanding of 
what is essential to plant growth, and the importance of balance.  I've been 
helping people sort out problems in planted tanks for a while now, and I 
can't _tell_ you the number of times I've talked to people who arbitrarily 
added light, [supplemental CO2, trace elements] (you can drop in which ever 
term you want!) without understanding the ramifications of what they were 
doing.  

Add CO2 without the light levels to allow the plants to use it, and at best, 
 you're wasting your money, at worst, you'll cause pH swings that seriously 
stree your fish.  Add light without first making sure nitrate/phosphate 
levels are low, and watch that algae grow!  Oh! you _did_ clean up the 
water?  The plants did grow well for a couple of weeks, and now they've 
stalled, and algae is growing? Check your pH levels.  Bet you'll find that 
the plants are exhausting the available CO2 by mid-day.  And trace elements! 
 I'm sure you've heard as many horor stories as I ahve about overdosed 
tanks.

> For instance, I have a 10 gallon tank with one big 4" fish and 40
> watts of lighting.  A clump of Java moss is the only vegetation.  The
> tank is pretty much algae-free, although by all accounts, it should be
> an algae soup.  It has stayed that way for several years.

Yes, and I guarantee that that fish is putting out plenty of CO2 for that 
Java Moss.  Bet you harvest it pretty frequently too.  One more question 
though...why?  Sounds like a waste of electricity to me!<g>

> I also have a couple of outdoor tubs that are in direct sunlight for
> part of the day, but have next to no algae.  In fact, these tanks
> produce some of my best plants, even better than the ones grown in my
> CO2-injected setup.

And again, I bet that the plants are to some extent allowed to become 
emersed, where they can extract CO2 from the atmosphere, no longer dependent 
on what is available in a small volume of water.
 
> In short, I'd say if someone wants high light in a low-tech setup,
> it's worth a try.

In long<g>  I'd say that if people want to start with an educated guess, 
rather than re-inventing the wheel every time they set up a tank, they need 
to understand the CONCEPT of balance, as well as keeping an open mind to the 
fact that there are a number of ways, and a number of LEVELS of achieving 
that balance. ;-)

Karen
--------------------
> Subject: Re: nutrient diffusion into vermiculite

Charley,

> * Do you see a need for directly taking nutrients directly to the
>   substrate to avoid high nutrient concentrations in the aquarium 
>   water?  (High nutrients in water could force an algae bloom; the 
>   substrate is low volume compared to the rest of the tank, and the
>   principle of diffusion suggests nutrient concentrations in the
>   substrate will merely achieve the same proportion as those
>   concentrations in the water.  In short, can we get the nutrients
>   in *sufficient quantities* where we need it, or *only* where we 
>   need it?)

You overlook the fact that although many of our aquarium plants (like the 
aforementioned Echinodorus<g>) feed directly from the substrate, many others 
 feed direclty from the water column.  If nutrients were not available in 
the water _nad_ the substrate, we would seriously limit the species of 
plants we could keep.  In fact, I've found the bits of Water Sprite that I 
leave floating in my tanks a very useful bellwether for trace elements.  If 
they start to look a little less lush and green, I know my trace elements 
are being used up too quickly.
 
> * Do you see a need for any type of substrate circulation?  (To
>   ensure even nutrient distribution, or minimize the eventual
>   restriction of substrate circulation due to mulm or debris
>   accumulation?
 
> Of course, we're looking for a tank that will last 5+ years.  :^)

While I am guardedly impressed by some of the things I'm seeing happen in my 
one tank with substrate circulation, (UGF/heater system) I also know that 
I've had several long term successful tanks without substrate circulation.  
I'm still of the oppinion that while mechanical substrate circulation (of 
whatever method) is probably of some benefit, it is not essential for very 
good long term plant growth.

Karen

> ------------------------------

> Subject: Re: Just an Idea (plenum)

Charley,

> *  We can fully remove any anaerobic activity from the substrate.  At the
>    first sign of anaerobic activity, simply open the valve and the plenum
>    is "injected" with oxygen.

My understanding is that we don't _want_ to remove all anaerobic activity 
from the substrate... that we _want_ a low O2 environment to allow for 
cation exchange of trace elements.

Karen