Â· Modern Use. Today, basalt is used to a lot of things. Most common use of. is as aggregates. Basalts that are crushed are used for construction purposes, like asphalt paving, concrete aggregate and rock filtering agents. Basalts are added as aggregates to increase strength to concrete. Modern Use. Today, basalt is used to a lot of things. Most common use of. is as aggregates. Basalts that are crushed are used for construction purposes, like asphalt paving, concrete aggregate and rock filtering agents. Basalts are added as aggregates to increase strength to concrete.
Typical filtration cycles are four hours, twice per day (for hot tubs operating a single or two speed pump). Reducing the cycles to 3 hours twice per day will save water pumping energy. These circulation times should be set for off-peak hours. (Some hot tubs have small, low wattage circulating pumps that run 24 hours a day. Typically these draw less energy than a 100 watt light bulb.
For these groups, the hot tub temperature should be reduced to around 100 degrees and they should spend no more than 15 minutes in the hot tub. Pregnant women should limit their exposure significantly, as soaking in water above 102 degrees can cause fetal damage or death, particularly in the first trimester.