i know robert chose this question to start a friendly debate, so i feel obligated to speak my mind
first off i would like to say that basically everything betty said about natural tanks is right on the money. but i think she didn't give high tech tanks a very fair summary. this is how i see it.
in a high tech tank you have 3 parts: Light, Fertilizers, and CO2.
it is my understanding that most Natural tanks have upgraded lighting, but it just isn't as high as a high tech tank. please correct me if i'm wrong.
so basically when you buy lighting, if you want a high tech tank, spend a few extra dollars and get the 3-4 watts/gallon.
this leaves us with co2 and nutrients. yes, a pressurized co2 system is very expensive, ranging anywhere from 100-300+ dollars. mine was about 230 dollars just for my 30 gallon tank.
fertilizers cost about 30 dollars for a 2-3 year supply if bought from
http://www.gregwatson.com .
so yes, high tech is more expensive, but well worth it if you ask me. when you compare a 500 dollar top of the line setup to some hobbys such as cars were you spend thousands just on 1 part.
now, as far as time/maintanance goes, i think a lot of people think that high tech people spend hours a week trimming. i can only speak for myself, but i have 4 high tech planted aquariums, and i spend around 2 hours a week on maintanance. this to me seems minimal considering the amount of beauty you get from these hours of work.
another BIG difference is plant selection. i can go out and get 95% of the aquatic plants i see on the net, and they will grow and do well in my tank. when you have a natural tank, your plant selection is very limited. i mean yes, there are tons of plants out there, but most of them (to me) aren't that appealing to the eye.
i hope i havn't upset anyone, or hurt any feelings. i am just trying to get this thread going a little more with my perspective on things.