Well water's the same as Groundwater like we have on L.I. The benefit is it usually has a lot of essential nutrients for your tank. It'll make it a bit harder than city water ... thus possibly a higher pH, but nothing your fish shouldn't adjust to. Continue with using de-chlorinator.
Below is an excerpt from the link explaining why you aerate well water.
Aeration of the water to oxidize the hydrogen sulfide gas, combined with periodic shock chlorination.
Since the bacteria that create the hydrogen sulfide odor (rotten egg) are usually anaerobic, or bacteria that cannot thrive in oxygen rich environments, often aeration in a non-pressurized vented holding tank is beneficial to eliminate and drive off the gas into atmosphere. This works best if the pH is low (less than 7.0) since the hydrogen sulfide gas at pH higher than 7.0 will not easily gas off completely.
Clean Water Store: How To Treat Odors In Well Water
75g Planted Barbs Denison, BlackRuby, Tiger, Albino Tiger, Green Tiger, Cherry, Gold, Checkered, Odessa.
NonBarbs Cardinal, Neon, RummyNose, Bloodfin Tetras, Z. Danios. 1RTS. Amano, Bamboo, Ghost & RCS. 20g Long Shrimp Tank RCS, Tiger, Amano.