Ammonia Sources
That should tell you where you can get ammonia from. I'm going to try and get the 'kleen off' product for cycling my latest tank. Apparently boots is a good place, and possibly Homebase (i havent tried either yet)
Ammonia is improtant as it basicaly fools the filter into thinking theres fish in the tank, but in reality there isnt, and therefore you wont have any deaths.
I think (im not 100% sure) you can do it with fish flakes, as when they decompose they'll create ammonia, although i'd strongly advise to actualy use ammonia.
Maybe someone can help me with this, but do FS sell ammonia? and if not wouldnt it be a good idea too as we all need it?