We often open our pool late (just did it last Sunday) and typically find the water green. We would then use the SLAM method until free chlorine maintains overnight two days in a row. However, the water would still be very green at this point and we cannot see the bottom at the deep end. In past years we used flocculant, which requires running the pump in recirculation mode for two hours, stopping the pump for eight hours, and finally vacuuming to waste. This worked great but used a lot of water and heavy physical efforts because we wanted to vacuum fast.
I'm curious if there is any alternative method to clean up the pool. We have a sand filter and this year we tried clarifier without flocculant, but now 1 qt clarifier used (we did four treatments of 6, 6, 10, 10 ounces) and six days later, the pool looks almost as green as before. Clarifier did increase the filter pressure by more than 10 psi overnight (compared to 1-2 psi without) but the effect of one treatment is probably just a single day. We are continuing to maintain FC at the recommended level and FC does not drop overnight, so it's just fine dead algae.
I read about diatomaceous earth. How much do people usually add? Do I just add DE on top of existing sand or do I have to remove some of the sand (i.e., is there a limit to how full the filter can be filled)? How often do I need to remove / replace the DE layer?
Any other recommendations?
I'm curious if there is any alternative method to clean up the pool. We have a sand filter and this year we tried clarifier without flocculant, but now 1 qt clarifier used (we did four treatments of 6, 6, 10, 10 ounces) and six days later, the pool looks almost as green as before. Clarifier did increase the filter pressure by more than 10 psi overnight (compared to 1-2 psi without) but the effect of one treatment is probably just a single day. We are continuing to maintain FC at the recommended level and FC does not drop overnight, so it's just fine dead algae.
I read about diatomaceous earth. How much do people usually add? Do I just add DE on top of existing sand or do I have to remove some of the sand (i.e., is there a limit to how full the filter can be filled)? How often do I need to remove / replace the DE layer?
Any other recommendations?