Thing is,even if your water company adds chloramines (mine does) and you use a sodium thiosulphate based dechlorinator (most of them) then this will neutralise the chlorine element and release the ammonia element of the chloramine into the water.Unless you have remarkably accurate instruments you will not be able to detect the incredibly small amount ammonia thus produced.
A mature filter will eat it as readily as the ammonia produced by the fish.A brand spanking new filter won't therefore,by using a sodium thiosulphate dechlorinator, you are contributing slightly to the accumulation of ammonia in the system.Under these conditions you may consider it worth while binding the ammonia and nitrite with a hugely expensive dechlorinator like Amquel Pond Plus.You will have to use it for several weeks for total peace of mind until the nitrate levels start to show a serious upward trend.Then you can be sure that the filter is mature and you can revert to a cheaper dechlor.
Other things to watch out for when using the binder type dechlorinators is,apparently, a massive drop in ORP readings and a degradation of the alkalinity (reportedly a very large,fast swing downwards in kh).So it's all about balancing the varying actions and reactions just the same as normal water keeping.
By far the best way to help your QT would be to increase the filtration and use mature media from the pond to get things moving rapidly.
Try a read of this thread,last post.
http
://koivet.com/forums/showthread.php?t=2 ... t=ammolock
If you really want a mind provoking read then try this one.A beaut but a long read.
http
://koivet.com/forums/showthread.php?t=21627