Just for the record: In conjunction with Seachem’s response too ZergyMonster, here are two more replies from Seachem—the first to Byron, the next to Abbeysdad.
Seachem: The nitrite is still completely available for the beneficial bacteria in the bio-filter to consume it. After 24-48 hours, when the Prime is no longer active, if the nitrites are still present and have not been consumed by bacteria, then yes, they will be re-released. Unfortunately, there is not a test kit on the market that will distinguish between the bound form of nitrites and nitrates and the unbound form. So the best option is to continue to add Prime every 48 hours until you are able to get a zero reading for nitrites. Most ammonia test kits out there are the same in that they cannot distinguish between free ammonia and total ammonia, simply giving you one reading for total. This can be misleading, especially when you are trying to cycle a new tank. Both our Multitest: Free and Total Ammonia and our Ammonia Alert, can distinguish between the two, making it much easier to know exactly what is going on inside your aquarium.
This is Abbeysdad’s question and Seachem’s response:
Abbeysdad: So why does the chemical bond that detoxifies ammonia, nitrite and nitrate fail after 24-48 hours?
It is perhaps a moot point in an established aquarium, but can be a large issue in a newer setup.
Would it be safe to add the recommended dose of Prime every 24 hours for an extended period?
Are there any negatives in doing this? In such a case, will the repeatedly dosed Prime become inert in the water chemistry?
Thanks for your attention.
Tech Support EH
Re: Prime questions...
Thank you for your questions, Abbeysdad. All water conditioners only have the ability to bind to ammonia, nitrites and/or nitrates for a limited period of time; Prime actually will do this for a longer period than any other product available. You're correct; in an established tank, the beneficial bacteria will consume these things within this time period. However, in a new setup or cycling tank, we recommend dosing Prime every 48 hours to keep the ammonia/nitrites detoxified. As long as you are using Prime as directed, there is no harm in adding it this frequently for an extended period of time. Every 24 hours should not really be necessary, as it will remain active for up to 48 hours. We hope this answers your questions!