I also use Amquel, because there are chloramines in my tap water. (I think the water co. mostly adds chloramine in the winter but I add Amquel all year to make sure.) Use Novaqua to dechlorinate some tap water, then do an ammonia test on that water. If you get an ammonia reading (my reading was .25) then you have chloramines.
Add Amquel at the dosage that the bottle says. If you follow the directions on the bottle for your tank size, and then only treat your new tap water at a water change, you won't hurt the cycling bacteria.