"Toni" wrote in message rthlink.net...
I have a 90g (24" deep) planted tank that I am wanting to maintain without
use of CO2.

My water is pH 7.0, KH 1, and I have 220 watts of CF lighting, (half 9325º
half 6700º). I have used Onyx sand as a substrate, and the tank is filtered
by an Eheim 2026 and a Penquin 330.

Well cut the light way back, 160w of NO FL lighting is about right.
Deeper 4 inch substrate is good.
You will have algae with this much light other wise unless you go to
CO2.

My hopes are to add Discus in the future
after the tank matures to some degree, so am dealing with warmer water. I
change 25% of the water once a week and replace with aged (outgassed) water.

Non CO2 tanks are choosen for less mainteance, this is part of the
deal, no water changes. Top off for evaporation only. Water change
when you need to do a big trim or cleaning, about once every 3-6
months or so.

82-84F works fine for Discus, breeding even......... so I know they do
fine at that temp. Also, these are big cichlids and folks have
troubles not over feeding them. All this waste and leftover food =
algae.
So don't over stock the tank, like 5 fish MAX if you plan on feeding a
lot.

I see you plan on adding a bunch of smaller fish on top of this.
This is going to produce a lot of waste and there's no way a non CO2
tank w/25% weekly water changes is going cope with this loading.

I know that some of these plants (i.e.the sunset hydro) may not do well in a
moderately lighted tank,

It's not the light directly, it's the CO2, the plants(just about any
plant you want to pick for that matter) will grow just fine if you
added CO2.
If you want to improve plants growth(you would not have asked
otherwise), then CO2 is your only logical next step here.

CO2 enriched tank can and do work great with 50% weekly water changes.
Many planted tank+ Discus owners do 50% 2x a week water changes FWIW.

and that there are design flaws... we'll let that
go for the moment.
My question is regarding nutrients- I have here Flourish Excel, Flourish,
Flourish Iron, Flourish Potassium, and Flourish tabs. I have a tab near each
of the swords and larger plants. I understand that my fish provide the N and
the P.

In a non carbon enriched tank somewhat.
You are adding Excel to a larger tank and will need to pay a fair
amount over the course of a year for this.

I'd recommend using CO2 gas tank for your goal here. It'll allow you
to feed more, have more fish, do water changes etc and have faster
growing plants.


Is there a "keep it simple stupid" method to keeping this tank presentable
without altering it's basic lighting/water/fish load ??


Sure, but your stocking list is critical, lighting value needs to be
lowered.
Deep substrate, lots of plants from the start, 10-25% surface with
floating plants like water sprite.

I prefer (at this point anyway) to buy prepared products. I know it is a
large tank and CO2 would be preferable, but until I get a handle on my KH
(hoping the Onyx sand will help)and grasp some basic water chemistry I am
staying away from CO2.

It'll raise the KH some, for awhile. It's better to add those PC
lights last rather than adding the CO2 tank last. But the Excel will
help some. It'll get costly along the way.

Building a substrate well is a key for the non CO2 method with a
decent lighting amount, 1.5-2w gal or so, no water changes.

I am not wanting excessive growth nor showstopping results. I am wanting the
majority of my plants to stay healthily green.
I do not mind dosing daily. I am just looking for that elusive "simple plan"
of what to add when.
Does one exist?

Both Discus and plants are more work than you may be prepared for.

Everyone says the same thing about nothing great on the plants or
wanting fast growth, they often come back asking about how to cure
their algae problems. Many Discus owners unwilling to try the CO2 and
other plant methods just live with their fur covered Anubias. Meantime
my fish are happy, get lots of water changes, high Dissolved O2
levels, and the tank looks nice.

Folks often think they have to apply strict discus breeder's habits to
their own tank. This is not true. Temp is one issue, low KH/Gh is
another, 3 degrees is fine, even up to 5 or so. I had them bred at
82F, GH 9 , KH 5.5.
Loads of plants and CO2.

They did not get any special treatment and were fed once a day(Varied
diet-no live tubifix worms) and got quite large 7-8".
Regards,
Tom Barr