RO/DI should not create ammonia as long as your source water doesn't contain chloramines, or if it does, you use a chloramine block on your RO/DI filter.
Chloramines = Chlorine+ammonia, chloramine blocks (catalytic carbon) break the ionic bonds holding the chlorine and ammonia molecules together, stripping out the ammonia and the chlorine. If your water is really dirty (high TDS) it can cause your DI resin to be used up fairly quickly. I have 2 DI canisters on mine and I have to replace them every 3 months because my tap water is really high in TDS (800+) but it doesn't contain chloramines, just chlorine. If you are really concerned you can add a few drops of Prime to the bucket to make sure you neutralize any chlorine and ammonia but I have never had to do that with RO/DI with proper filters.
Chloramines = Chlorine+ammonia, chloramine blocks (catalytic carbon) break the ionic bonds holding the chlorine and ammonia molecules together, stripping out the ammonia and the chlorine. If your water is really dirty (high TDS) it can cause your DI resin to be used up fairly quickly. I have 2 DI canisters on mine and I have to replace them every 3 months because my tap water is really high in TDS (800+) but it doesn't contain chloramines, just chlorine. If you are really concerned you can add a few drops of Prime to the bucket to make sure you neutralize any chlorine and ammonia but I have never had to do that with RO/DI with proper filters.