Originally Posted by BWG
Please, please, please show me where this has been the case. I am begging you! You've stated this several times on here so I'd really love to know!
You know what a quick Google search on the topic showed me? Prime Overdose -vs- Oxygen - Seachem Support Forums
Originally Posted by that refrenced forum a post by seachem
Thank you very much for pointing this out to us; we hope to help clear up this issue and would truly appreciate you passing the information along once receiving it. All water conditioners are reducing agents; reducing agents will "reduce" whatever is available within the aquarium. For example, it reduces chlorine(Cl2) to two separate chloride molecules. Though the potential to reduce oxygen is there with any reducing agent, this is very, very rare. Prime can be safely overdosed up to five times the recommended amount in an emergency situation. Doing so is very safe, and it would take a massive overdose to have any effect on the oxygen levels in the tank. Because Prime only works for 24-48 hours, its effects do not build up over time. Hope this helps! Please let us know if you have further questions.
Although they poo-hoo the effect they do admit it in fact does reduce oxygen.
As I stated before the danger is you dose Prime (or any other dechlor or ammonia lock) and you still test ammonia. Even if that first dose completely locked up the ammonia.
So you dose again. test ammonia does again etc etc etc.
All the while locking oxygen. As Seachem admits above.
so you can suffocate the fish even if seachem doesn't want to admit it.
All the while only the first dose was required.
These type chemicals have side effects.
To me it is better to add fast growing plants to consume the ammonia while also sucking out carbon dioxide and returning oxygen. In that case the side effect is a healthier aquarium.