CO2 advice?

[Richer]

I would personally suggest a pressurized system for any tank. Even though a pressurized system is a lot more expensive in terms of intial costs... in the end, it will more than pay for itself. My 5 lbs CO2 tank lasts about 6 months before it runs out (on a 70gallon tank). Refills cost 10 bucks. I did have a DIY system on an old 15 gallon tank that I had... it was a pain. I had to replace the bottle every week, and the CO2 output was difficult to control. Plus the smell of the CO2 generator wasn't all too pleasant neither. Using a jello based recipi would increase the lifespan of a CO2 generator by a couple of weeks. If I forgot to replace the CO2 generator, or if I went on an extended holiday, my tank would suffer. If you do decide to try out the DIY method on your tank, I would suggest 2 CO2 bottles, 1 may not generate enough CO2 for a 30 gallon tank.

I would bother using bubbles/second as a baseline for CO2 injection. As said before, the amount of bubbles/second needed for a tank is completely dependant on surface aggitation, plants, etc. Using a pH and KH table is the best way to go about it.

-Richer