While I really do appreciate your comments, I am still afraid of CO2. I'm
afraid of ugly tanks and tubing in my home, I'm afraid of compressed gas,
and I know I'll not know how to hook it all up. I'll bang the tanks
against
my walls lugging them in and out and the gauges will confuse me.

It's understandable that you would have those fears, but with a low pressure
needle valve, I've run my tanks, plum empty and never had a problem.... I
mean empty....

And hooking them up, is pretty simple after it's assembled.... most of them
are preassembled if you buy the 'set' and that is recommended for the first
time user.... I was too, spent way more than I should, but it's a great
regulator, and Ive never had better plant growth....

For your 90g, I'd think a 10lb bottle would fit nicely behind a cabinet,
tubing can be routed anywhere, and can be hidden pretty easily...

Think about the benefits, analyze the cost, measure the risk, and go buy
one... haha....


There is nothing for me to do now but set out on my *very steep* learning
curve.
Thank you for the time it took to formulate your response.

--
Toni
http://www.cearbhaill.com/aquarium.htm