Trouble finding Aeration timer for septic system

I have a unique situation. I am on city water and live on a hill. Water pressure was so greatly reduced coming up the hill, the original owner installed a pressure pump and tank. It works well to boost the pressure, however, since I moved in, the water has had a strong sulfur smell. The system was shock-chlorinated and that took care of the sulfur smell for now. Now, however, I have a strong chemical or metalic taste and smell coming FROM THE PUMP OR TANK. I can bypass the pump and tank, and the water tastes and smells ok coming directly from the city (but has less than 20 psi). What has happened in my pump or tank to cause this chemical/metalic taste and smell? Did the chlorine damage the bladder, pump, or pipes? Do pumps, bladder tanks, and associated plumbing ever impart a strange taste due to the materials used? Should I replace anything? Technical info: 82 gal pressure tank with bladder, 5 years old, 1/2 hp pump, mixture of brass, copper, pvc, pex, and galvanized steel tying pump, tank, and water main together. Water from city has at least 1-3 ppm iron.

The water from my private well stinks like rotten eggs. Searched the internet for solutions, came across this site Pure Intake, [url]www.pureintake.com[/url]. Claims to be able to rid the water smell, all you need to do is buy the booklet for $2.95. Interested as all thats required is about $5.00 in supplies. Any experience with this....always great advice - Many thanks