I have used the MP-1 Tablets,quite a few times,& They work well!It's a 4hr wait time for Correct effectiveness per 1 liter of Non-turbid or Tepid water.I've found,Having Multiple Containers,Works best,though I have used a 4-liter container once,with 4-tabs at 1 time,& Noticed a slight Chlorine taste,Similar to L.A. Tap water.