Why can't good filtration take care of the TDS and other things that build up in the water?
How about this product that is advertised on AC -
http://www.aquaripure.com/testimonials.htm?gclid=COD4hc_DyJ8CFZMK5Qod1BBPtg
I have asked about using a RO system before but was told basicly that it would remove the trace elements, which would be bad.
I think the OP has found that not doing a WC for over 2 years has not caused him to lose any fish. I am sure he is unable to add any fish as his fish have become used to the toxic nature of the water. His fish will have a shorter life and most likely be stunted.
I also agree with the OP and a few others that over feeding is one of the major issues in keeping fish, much more of a bigger problem IMO than WC and overstocking.
I know I have gone long periods without doing a WC and I have done weekly WC for a long period.
As far as fish being happy? Treating fish humane? Might as well join PETA folks. If we truely cared about the fish being happy, we would not keep them in glass boxes for our enjoyment, we would leave them alone. We do the best to keep them alive and healty - for our enjoyment.
Want to know about fish happiness and humane treatment, look how they are bred and shipped. If dogs were handled like fish, lots of people would be going to prison.
How about feeder fish feelings, I am sure they are not too happy. Betas also.
If the OP does not want to do WC, well that is their right. My biggest and most expensive fish loss was during a WC that I forgot to treat the water - not a good time at all.
I hope the OP continues to be a part of AC.