Tom,

This was a very interesting post. I currently have a 30 gallon tank with pressurized co2. I'm in the process of setting up a 50 gallon tank. I was planning to move my co2 setup to the 50 and trying excel on the 30 which now has the pressurized co2. My 30 is running very well and is free of algae except for a few spots of gsa. I haven't had to scrape off algae on the glass for almost 3 weeks, so I'm a pretty happy camper right now.

My question is am I setting myself up for an algae problem if I switch the 30 to excel ? I'm not adding co2, but I am adding carbon so maybe this is a different situation. I could try excel on the new 50, but it obviously is more expensive. Should I just leave the 30 alone ?

Your comments on the stability of co2 levels caught my eye. For those using DYI co2 one of the problems is the inevitable variation of co2 levels. Is this another algae issue ? It almost seems that going excel or the Walstad route might be better with respect to managing algae.

One thing I think I've learned is that algae is not really related to too much of this or that. It's the relationship and interraction of nutrients that really seems to count. Phosphates are good for plants. Phosphates with little or no nitrates are good for algae.


Henry Hatch