co2 system question

[kevinly]

im about to start on a planted tank for my 30 g and i was wondering what is all the equipment i need for a co2 system. i know i need a co2 tank, regulator and reactor....is there anything else i need? also how does the diy co2 work for you?

[Complexity]

If you can afford injected CO2, then just get it. Nothing compares with injected CO2. You can try DIY if you're on a tight budget. It works if you stay on top of it. Some people have created very nice DIY setups with dual 2liter bottles, etc.

However, if you can get injected CO2, you'll be very thankful. You have everything you need on your list already; however, I'd also consider getting a pH controller. I find they help with a couple of things. First, it ensures a steady level of CO2 at all times. No problems with it getting too high or low periodically throughout the day or night. Adjust the pH that works for your tank and walk away. Just check on it every now and then.

Second, and perhaps most important, I find that it prevents the deadly "end of tank dump" which is what happens when the CO2 cylinder runs out of CO2. The pressure drops so low that it no longer registers on the regulator properly. When this happens, it's not uncommon for a last burst of CO2 is flooded into the tank. Unfortunately, this often kills the fish. The pH controller won't allow that to happen because it will turn the regulator off once the pH level reaches what you've set. Even if the regulator wasn't registering the CO2 pressure correctly, it cannot inject CO2 if the pH controller has cut it off. I've gone through 3 "end of tank dumps" with no adverse affects which I contribute to my pH controllers.

Caveats: You will need to clean the electrode and recalibrate it. You're supposed to do it weekly, but I'm terrible and don't do it but every few months. When I finally do clean and recalibrate it, it's a very quick and simple job.

Second caveat is that the electrode will eventually wear out and need to be replaced. I think they're around $75, give or take. Correction, price is lower, around $35. I've been told they need to be replaced about every 18 months or so.

Even with those caveats, both of which are in regards to the pH controller, I wouldn't even consider DIY CO2 if you are wiling and able to afford injected CO2. However, if injected CO2 just isn't in the budget, then DIY can be rigged up. The success of it is mainly dependent on how much effort you put into it the design and maintenance.

Regarding reactors, before spending a fortune on a fancy one in a box, consider a Rex-Style reactor that's made of PVC. It's super easy to make, inexpensive, and works great.

[wesleydnunder]

+1 to Vicki's post.

When I bought my regulator/solenoid/needle valve I wanted something that would last and have solid, consistent accuracy, so I ordered one from ADG. I wasn't disappointed.

I built a reactor from Rex Griggs' site. As vicki stated, easy to build and works great. I made a couple mods to the original design to make it easier for me to use and clean.

I also bought my brass check valve (an absolute MUST, IMO) and co2 tubing from Rex.

I get refills at a local welding supply shop for about 9 bucks.

Mark

[Complexity]

Yes, I forgot about the check valve and CO2 tubing (as compared to regular air tubing). I also use a brass check valve. It's a must.

My local refills for my 10g cylinder was $5 last time, but it was closer to $9 the time before. I think the guys are dropping the price just to be nice (I'm getting to know them a little as I come back more often). I get mine refilled at the AOC in Rosenburg.

http://www.aocweldingsupply.com/