Deep Blue Pro Calcium Hardness Plus - If the calcium hardness of your spa water is less than 100mg/l then it should be increased using Deep Blue Pro Hardness Plus.\nCalcium Hardness:Calcium hardness (or total hardness) is the measure of how hard or soft the water is. The level will vary depending on where your water supply comes from, for example in some parts of Scotland & South Wales the water is very soft and in the South East the water can be very hard. The hardness depends upon the amount of mineral salts (mainly calcium) that are dissolved in the water and the more salts there are the harder the water is.\nProblems Associated with incorrect Calcium Hardness Levels:\nLow Hardness – Corrosive waterLow Hardness – Etching of surfacesLow Hardness – FoamHigh Hardness – Scale formationHigh Hardness – Filter calcificationHigh Hardness – Cloudy waterHigh Hardness – Staining\nIdeal Ranges:Low calcium Hardness less than 100mg/lHigh calcium Hardness more than 200mg/lIf the calcium hardness of your spa water is less than 100mg/l then it should be increased using Deep Blue Pro Hardness Plus.\nDose Rates:To Increase Hardness in 1,000 Litres by 10mg/l requires 15g of Hardness PlusTo Increase Hardness in 1,000 Litres by 25mg/l requires 38g of Hardness PlusTo Increase Hardness in 1,000 Litres by 50mg/l requires 76g of Hardness PlusIf the calcium hardness of your spa water is greater than 200mg/l then Deep Blue Pro ScaleAway should be used to help prevent scale deposits within the filter, heater, pipework and on spa surfaces.\nDose Rates:To reduce hardness in 1,000 Litres requires 25ml of ScaleAway – Repeat every 24 hours untill your levels have returned back to normal range.