Maybe your body is too addicted to the enemas? Never heard of someone having this problem with Oxypowder before. I vaguely remmeber reading on their website some people are low on some kind of stomach acid and something about fresh grapefruit juice helping.. might want to look that up on their website.
Are you taking the oxy near/around food?
I wait a couple hours and pop them a few minutes before going to bed. I only drink about 10oz of water with it.
I usually have to "go" first thing in the morning..athough its not urgent enough to wake me up. If I eat fruit for breakfast that definitely starts the process of it moving out.