Hey all, I just got some MP1 tablets yesterday and got a chance to try them out on a hike, and was wondering why it takes 4 hours for the water to purify.

If you havn't tried them yet, the water gets green, then clear and ends up tasting like diluted pool water so they are not nearly as bad as iodine tabs...

Does anyone know why it takes 4 hours??

Thanks!

The 4-hour requirement is only for a worst case scenario. Unfortunately, the EPA has chosen to not allow the consumer easy access to this information. See below the instructions I include with MP1 tabs in my survival kits and vests, taken from the EPA test results:

For 70 degree water, next time I will probably only let it "marinate" for an hour... If it is clear... Thanks Doug!

I only wait an hour, and I use them regularly while backpacking. If you take the lid off the bottle at the end of the hour and let it "air out" for even five minutes, the chlorine taste dissipates almost completely. It ends up like tap water, or even a bit better.

Yeah, I really liked it, I just wanted to be safe seeing how it was my first time using purification tablets...

I really like them now

You might want to consider the MSR MIOX pen if you're going to use a lot of tablets. Over the long term you'll save money. It's virtually the same chemical and the wait times are the same if not better.

yeah... i dnt filter enogh to make it viable for me...

If you have a spare container you can pour the treated water back and forth between the two containers. This will improve the water's taste by both releasing some chlorine and through added aeration.