1. Time: It’s been 4-6 months since you first installed PoolRx.
2. Your chlorine demand goes back up to where it was prior to installing PoolRx.
3. Your water is cloudy, or you start to see algae

Note: Because a small amount of minerals are still working in the water you will notice a gradual change over about a two week period. This gives you plenty of time to add a booster or new PoolRx unit. Reminder: The minerals are used up from Algae kill, backwashing filter cleaning and splash out. The more these factors happen, the shorter the lifespan of the minerals.