SO this post is to get an idea if i am good with all my readings in my tanks and if i need to change anything.
I recently (10/10/11) upgraded to a 20 gal from my 10 gal. Everything was transfered over..gravel, plants, filter, rocks and such. I added about 16 pounds of more gravel as well. Previous to my tank change i had
Amm 0
nitrites 0
Nitrates around 5-10
Ph was in the 7 range

After the tank change 10/15/11 (5 days after)
amm 1ppm
nitrites 0
nitrates 10
Ph today 6

Chems i have in the tank..Store bought water with RO/DI and some other things. Ive read this is void of minerals needed by the fish.
CO2 DIY- 2 bottles and it is pumping out the CO2. Im guessing this is why my Ph has dropped versus when i had Ph in the 7 range with just one bottle.
Added today for the first time for the plants Seachem Flourish.
Also added today 3 capsules with 12 pellets each of Osmocote.
I had the Osmocote in my tank before this and i think it made the Nitrates rise to 40-80ppm.. kinda hard to get a perfect reading in the API masterkit as the 2 oranges look so similar, although it did seem the plants really liked it.
I dont know what my GH or KN (not test kits) is but from my reading a high Ph will be proportionate to a higher GH
Ex. High ph = high gh, low ph = low gh.. (or is it Kh)
Also i add when doing the PWC Jungles Start Right..5Ml for a 10 gal PWC. Ik now RO/DI has no metals or Chlorine but im anal. Should i delete this from my routine? Is it removing anything from RO?DI water i/fish need?

Since i use RO/DI water that is store bought do i need to add anything to add minerals back in the water for the fish, plants, ect?
Should i do say a 5 gal store RO/DI water coupled with 5 gal tap water?
To get this as i forgot i tested my tap Ph about 3 minutes out of the tap it was roughly 7.6 Ph.
I know a rapid Ph swing/change is harmful so i wont do anything today but say for my next PWC (biweekly changes) would a X%/X% or tap and store water be a waste or benificial to the tank environment?

Basically im looking for advice on what needs to be changed and what is good practice. I want to please everyone (fish/ plants) and need to know what is wrong and right in my practices.

Thanks all.. Be my Yoda

I see nothing wrong with what you're doing, but if you do want to continue to do 100% with RODI water, you should put the minerals back that the fish need (calcium, magnesium, etcc). Seachem makes a product called Equillibrium or you could pick up any of a number of GH booster products available. It is easier IMO, to do 50/50 RODI/tap. You'll usually get back in the water what you need.

JR, again.. Much thanks. WWould doing a 50 50 with tap water introduce tomuch Nitrates. Meaning nitrates with FLourish, the Osmocote and i think we have Nitrate...hold on let me see...
Ok this is my tap water break down

2008 tested
Lead 8 parts per billion
Copper 1.3 ppm

2010 tested
Arsenic 6 ppm
Barium .007 ppm


Free Chlorine .43ppm Monthly test
Chlorite .99 ppm daily test
Chlorine Diocide 660 ppb daily test

2010 tested
Sodium 16.8 ppm
Sulfate 7.1 ppm
Iron 70 ppb

2010 test
Manganese 250 PPb
Radon pCi/L 290-1300 quarterly tested
Chloroform 2.1 ppb

2009 tested
Nitrate 2.6 ppm

Ok so i know this is anal but this will give me back the needed minerals? Also that nitrate wont be to much to produce algea or whatever else?
Ok so no nitrates in FLourish but Osmocote has
"total nitrogen 19% derived from 10% Ammoniacal nitrogen and 9% nitrate nitrogen." The way i read that its in each pelet and i have roughly 36 pellets in total.
Also Jr, my Ph is not bad at 6?

ok now you can call me an OCD anal aqaurist

I guess an API test of your tap shows 0 nitrate? If it does show 0, no worry. A low level however, may not be so bad. If you don't think it has the needed nutrients you can always add some back in, but not sure I would do that.

A ph of 6 after you've been injecting CO2 is fine. Not sure how much lower I'd go though.

Jr i didnt do a nitrate test on the water yet. I will in the morning. The 6 for my ph is as low as i hope it goes. I wish it would raise a bit higher even in the 6.5 range. 6 scares me as im close to that real acidic line and dont want dead fish