Gin and tonic plasma levels at the lower limit of therapeutic efficacy and may, in fact, cause transitory suppression of parasites". This method of consumption of quinine was impractical for malaria prophylaxis, as the amount of drug needed "can not be maintained with even large amounts of tonic". The authors conclude that it is not an effective form of treatment for malaria. In Spain, a variation on the drink called Gin-Tonic has become popular. This differs from a traditional gin and tonic as it is served in a balloon glass (copa de balon) or coupe glass with plenty of ice and a garnish
Hard water the effects of hard water on the surfactants. For this reason, water softening is often unnecessary. Where softening is practised, it is often recommended to soften only the water sent to domestic hot water systems so as to prevent or delay inefficiencies and damage due to scale formation in water heaters. A common method for water softening involves the use of ion exchange resins, which replace ions like Ca by twice the number of monocations such as sodium or potassium ions. Washing soda (sodium carbonate - NaCO) is easily obtained and has long been used as a water softener for