C02 thoughts.

Basically with a co2 system, I would use a airstone to release the c02 into the tank? I dont have to mess with anything else, but set the c02 flow rate and leave it more or less? No yeast?
 
The plants don't normally run the PH down. CO2 will lower your ph for the most part, and if the plants are not getting enough CO2 some of them will scavenge calcium bicarbonate out of the water, which will lower your KH and the water's buffer (i.e., less CO2 can be held in the water). Without enough calcium carbonate in the water, you are subject to pretty decent ph swings. When the plants pull the CO2 out of the water during the day, the ph will rise. During the night, it will go back down. I went through this over 2 years ago, and that was why I went to pressurized CO2. The KH of the water was 0 and it comes out of the tap at 2 to 3.
 
You are going to have to do a lot more research on this subject. I spent weeks reading about it before going the pressurized route, and still missed the drop checker matter until a month or so ago. Granted, I was using Red Sea's drop checker with the tank water in it, and couldn't understand why my fish were gasping for air but the solution in the Red Sea drop checker was still blue. So, i chucked the entire thing in the trash. Last month, I learned the reason for that 4dKH water and not aquarium water needs to be used.

I have my pressurized CO2 system hooked up to diffusers in the water to make sure that all the CO2 is dissolved and not wasted. Going the airstone route might work if it makes really small bubbles, but with the diffusers I hardly if ever see any bubbles coming out of them (i.e., the CO2 is completely diffused into the water). Short term, the airstone would be cheaper, but it will cost you more in CO2 in the long run. Kind of the same principle as a large CO2 tank versus a small one. Right now, I am debating the purchase of a 35lb or 50lb tank because I am el cheapo in the long run.
 
I understand, In that case I will go with the diffusers as If im goign to spend money I want the best.

Can anyone share some links that could be helpful on how a C02 pressurized system works, hooks up, the different methods, and or parts to use?
I would like to read and learn about the bubbles per second deal etc.
 
Here is a link to a pretty straight forward Red Sea system:

http://www.redseafish.com/co2_pro.asp

Me, I went with something a little more complicated. I used the Milwaukee regulator/solenoid and the Milwaukee ph controller. Essentially, the ph controller turns the solenoid on/off based upon the ph level of the water. Mine is set at 7.2 right now. If the ph hits 7.3, the controller turns on the regulator and it runs until the ph hits 7.2. You can buy the ph regulator/solenoid and not use the ph controller until later on. You will just have to plug and unplug the solenoid into an outlet. I also went with the Milwaukee solenoid/regulator because it allows me to use the needle valves/bubble counters that I want to use and it allowed me to go from 1 needle valve/bubble counter to 3 needle valves/bubble counters and 3 diffusers. I could actually go to 6 pretty easily with the purchase of a different manifold and additional needle valve/bubble counters, but 3 is good for me for a while.

Here are some links:

http://www.milwaukeetesters.com/
http://www.milwaukeetesters.com/SMS122.html
http://www.milwaukeetesters.com/CO2regulator.html
http://www.co2-canisters.com/index1.html
http://cgi.ebay.com/3-way-Brass-Co2...ptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116

I also use the Red Sea 500 diffuser.
 
One seldom mentioned bit - if you're going to put it together from parts, consider a 2 stage regulator - they can be had on ebay pretty cheap for gently used ones and even a new one now & then. A 2 stage one will help reduce the "end of tank dump" that happens to an occasional user who lets his CO2 tank get too low before swapping it out.

I've got a Victor 2 stage one waiting to go into service. There are other good brands out there too.

Also - if you get a solenoid via ebay, you want one that can plug into a clock timer (so, 120V, not 12V dc) and that is normally closed.

Needle valves - this part, and the regulator are where you have to spend a little time on research & know what you're getting...
 
When I said "you'd need around 3 gallons", what I meant was "don't be silly, this is way too big for DIY".
 
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