New Plant Tank Update & RO/GH/TDS

Hello everyone. Thanks to helpful advice here and my obsessive research, my
recently converted 55g tank is almost overgrown with a beautiful Southeast
Asian biotope of flora and fauna. BTW, I have never seen the fish, which
include Rainbowfish, Gouramis, Loaches, Rasboras, and a Queen Arabesque
pleco, so colorful, lively, and seemingly happy .

O2 levels get to 110% saturation during the day and I have not had (for 5
weeks now) any serious algae threats (except for the darned diatoms I've had
for the last two years because my tap water has always had very high
silicates). Much of the flora has already doubled in size including the
Rotala Indica and Ulvaceus Apon, which if I didn't cut almost daily would
occupy the entire tank. The Madagascar Lace plant, which I started as a
bulb, already has a number of delicate 8" lacy leaves and beautiful runners
to the surface with pretty red floating leaves. Some of the balansae has
not done well while others have and the Giant Hygro seems to be shedding a
lot of leaves but still plenty of new ones. The four-leaf clover continues
to produce many four-lobed leaves and the runners are trying to occupy the
entire tank. The Java Ferns and Crypts seem to be doing fine with some of
the Crypts a deep red from the added iron (I assume). The only worry is
that these plants (and the onions) have "dirty" leaves with what I assume is
the diatom algae (it wipes off with the fingers). Also some of the Vals
have melted but much of it has rooted and is already laying across the
water's surface. The tank is about 75%-80% planted.

My conversion of the tank included the following:

- 130W PC fluorescent 4" above a replaced glass panel top (I have kids),
6700K full-spectrum bulbs (12 hrs.).
- 50/50 fluorite/gravel with flourish tabs every 5" for substrate.
- Pressurized CO2 injection with an electronic solenoid, Pinpoint pH
controller and a DYI reactor inline with my Magnum 350 Pro canister filter.
- I've modified the filter outlet to sit 4" below the surface of the water.
I've also replaced the activated carbon I used to use with Seachem Renew
which is not supposed to strip the water of trace elements (I know, a
controversial topic). I also left the biowheels on the filter in operation
but constricted the water flow to a mere trickle to keep the CO2 in the
water.
- Added chelated Fe and Flourish liquid supplement.

Today's readings:

pH: 7.01
dKH: 6.1
CO2 (calculated): 18.1 ppm
GH: 120 ppm
Fe: 0.5 ppm
Ammonia: 0
Nitrite: 0
Nitrate: 1.0 ppm
Trace: 0.05 ppm (I know, low. Considering overdosing Flourish).
No phosphate test.
Temp: 77
O2: 9 ppm

Okay, finally the water question. I was at first mixing my tap water with
RO water 50/50 to get my KH and pH down so I wasn't having to inject so much
CO2 to drive the pH from the usual high tap level of 8.2-8.4 down to 7 in
order to get enough CO2 dissolved in the water. This all seemed fine until
Carl at the LFS convinced me I should be using straight RO water
reconstituted with RO Right. Thinking it through, it seemed like a good
idea, giving me precise control over the water chemistry and at least taking
care of the high silicate problem, if not other algae inducing solids.
Although I have to tweak the KH with sodium bicarbonate, the RO Right is
supposed to provide the GH with neutral sodium, magnesium, and calcium
salts. The problem is that you cannot test the GH of this reconstituted RO
water with a standard test kit. I proved this to myself by testing a gallon
of reconstituted water starting with the recommended dosage for "medium
soft" water all the way up to 4 times the "hard" water dosage. Even at this
level, I could not get a reading with my standard GH test kit. I could
however get a reading just fine with the tank water. It is after all, still
mostly tap water at this point (it takes a lot of 25% water changes to get
the level to 95% reconstituted RO water). In fact, it notes the problem
right on the RO Right bottle:

TDS includes all ions in solution. It is better measured electronically or
by conductivity meter. General hardness or GH tests usually only measure
calcium & magnesium content and are a poor substitute. Do not greatly
exceed the recommended teaspoons even if your test indicates different!

So what is my GH? Do I really need a TDS or conductivity meter? I also
read in the archived newsgroups that although very low TDS most certainly
indicates soft water, high TDS does not necessarily mean high GH (meaning I
could be measuring other non-GH type solids, sodium?). Does that mean a
conductivity meter is better. Would one of those $50 jobbies be okay from
DFS?

Now the real question: Am I doing my usual over-obsessing and worrying
about something that is probably fine?

Arnim