In the last few weeks I've purchased brand new bottles of hydrogen peroxide from different local pharmacies. Bottles were sealed. After removing the seal and spilling a small amount on my hands or in the sink there are no bubbles formed at all. As I understand it, that means that it is no longer viable and is only water. I'm guessing that's why I haven't seen any affect when using it in the past against cyano or dinos. Anyone else have this issue? Can someone suggest a reliable place to buy some?