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Chlorine comes in many different forms, gas, liquid and solid. With a domestic tank the simplest form to use would be high volume chlorine tablets sufficient for the amount of water in the tank. It would also be possible to use High Test Hypochlorite granules (HTH) which are often used in swimming pools or a liquid domestic bleach or disinfectant. Each form has a different available chlorine content and it is useful to make up a standard 1 per cent chlorine solution (10g of chlorine/litre of water or 10,000mg/litre or 10,000 parts per million). This also ensures that solid forms of chlorine are fully dissolved before being added to the tank. The quantities of common forms of chlorine needed for a 1% solution are shown below.

SAorry, the tables do not seem to have formatted very well but you should be able to unscramble them.

Chlorine Source Available Quantity Approximate Chlorine % Required measure High test hypochlorite (HTH) granules 70 14g 1 heaped tablespoon Bleaching powder 34 30g 2 heaped tablespoon Stabilised tropical bleach 25 40g 3 heaped tablespoon Liquid household disinfectant eg Domestos 10 100ml 7 tablespoons Liquid laundry bleach 5 200ml 14 tablespoons Antiseptic solution e.g. Milton, Javal 1 1 litre 1 litre Chlorine tablets e.g. Aquatab 60-70 14g Tablets specify

Enough chlorine must be provided to disinfect the water completely and to leave a free residual chlorine level in the water of 0.2-0.5mg/l. The chlorine residual level can be accurately measured with a simple colour comparator device but as a rough guide the free residual level is at the top of the right range when chlorine becomes detectable in the water by taste or smell. The dose of chlorine to add to achieve the desired free residual level depends on the quality of the water. If there is a high load of suspended solids, more chlorine will be needed. It is however usual that chlorine should be added in the range of 1–5 mg/litre. The amount of the 1% chlorine solution described above needed to achieve this range of chlorination are shown below.

Desired Chlorination Level 1,000l 2,000l 5,000l 6,000l 8,000l mg/l tank tank tank tank tank 1 0.1 l 0.2 l 0.5 l 0.6 l 0.8l 2 0.2 l 0.4 l 1.0 l 1.2 l 1.6 l 3 0.3 l 0.6 l 1.5 l 1.8 l 2.4 l 4 0.4 l 0.8 l 2.0 l 2.4 l 3.2 l 5 0.5 l 1.0 l 2.5 l 3.0 l 4.0 l

This chlorine should be allowed to run through the pipes so that they are also disinfected and then left to stand for at least 30 minutes as this contact time is necessary for it to kill all of the pathogens. Chlorine evaporates from a free water surface so water that is left in the tank will gradually reduce in chlorine content.

Chlorine comes in many different forms, gas, liquid and solid. With a domestic tank the simplest form to use would be high volume chlorine tablets sufficient for the amount of water in the tank. It would also be possible to use High Test Hypochlorite granules (HTH) which are often used in swimming pools or a liquid domestic bleach or disinfectant. Each form has a different available chlorine content and it is useful to make up a standard 1 per cent chlorine solution (10g of chlorine/litre of water or 10,000mg/litre or 10,000 parts per million). This also ensures that solid forms of chlorine are fully dissolved before being added to the tank. The quantities of common forms of chlorine needed for a 1% solution are shown below.

SAorry, Sorry, the tables do not seem to have formatted very well but you should be able to unscramble them.

Chlorine Source Available Quantity Approximate Chlorine % Required measure High test hypochlorite (HTH) granules 70 14g 1 heaped tablespoon Bleaching powder 34 30g 2 heaped tablespoon Stabilised tropical bleach 25 40g 3 heaped tablespoon Liquid household disinfectant eg Domestos 10 100ml 7 tablespoons Liquid laundry bleach 5 200ml 14 tablespoons Antiseptic solution e.g. Milton, Javal 1 1 litre 1 litre Chlorine tablets e.g. Aquatab 60-70 14g Tablets specify

Enough chlorine must be provided to disinfect the water completely and to leave a free residual chlorine level in the water of 0.2-0.5mg/l. The chlorine residual level can be accurately measured with a simple colour comparator device but as a rough guide the free residual level is at the top of the right range when chlorine becomes detectable in the water by taste or smell. The dose of chlorine to add to achieve the desired free residual level depends on the quality of the water. If there is a high load of suspended solids, more chlorine will be needed. It is however usual that chlorine should be added in the range of 1–5 mg/litre. The amount of the 1% chlorine solution described above needed to achieve this range of chlorination are shown below.

Desired Chlorination Level 1,000l 2,000l 5,000l 6,000l 8,000l mg/l tank tank tank tank tank 1 0.1 l 0.2 l 0.5 l 0.6 l 0.8l 2 0.2 l 0.4 l 1.0 l 1.2 l 1.6 l 3 0.3 l 0.6 l 1.5 l 1.8 l 2.4 l 4 0.4 l 0.8 l 2.0 l 2.4 l 3.2 l 5 0.5 l 1.0 l 2.5 l 3.0 l 4.0 l

This chlorine should be allowed to run through the pipes so that they are also disinfected and then left to stand for at least 30 minutes as this contact time is necessary for it to kill all of the pathogens. Chlorine evaporates from a free water surface so water that is left in the tank will gradually reduce in chlorine content.

Chlorine comes in many different forms, gas, liquid and solid. With a domestic tank the simplest form to use would be high volume chlorine tablets sufficient for the amount of water in the tank. It would also be possible to use High Test Hypochlorite granules (HTH) which are often used in swimming pools or a liquid domestic bleach or disinfectant. Each form has a different available chlorine content and it is useful to make up a standard 1 per cent chlorine solution (10g of chlorine/litre of water or 10,000mg/litre or 10,000 parts per million). This also ensures that solid forms of chlorine are fully dissolved before being added to the tank. The quantities of common forms of chlorine needed for a 1% solution are shown below.

Sorry, the tables do not seem to have formatted very well but you should be able to unscramble them.

Table 1 – Quantities Required for a 1% Chlorine Source Available Quantity Approximate Chlorine % Required measure High test hypochlorite (HTH) granules 70 14g 1 heaped tablespoon Bleaching powder 34 30g 2 heaped tablespoon Stabilised tropical bleach 25 40g 3 heaped tablespoon Liquid household disinfectant eg Domestos 10 100ml 7 tablespoons Liquid laundry bleach 5 200ml 14 tablespoons Antiseptic solution e.g. Milton, Javal 1 1 litre 1 litre Chlorine tablets e.g. Aquatab 60-70 14g Tablets specify Solution

Enough chlorine must be provided to disinfect the water completely and to leave a free residual chlorine level in the water of 0.2-0.5mg/l. The chlorine residual level can be accurately measured with a simple colour comparator device but as a rough guide the free residual level is at the top of the right range when chlorine becomes detectable in the water by taste or smell. The dose of chlorine to add to achieve the desired free residual level depends on the quality of the water. If there is a high load of suspended solids, more chlorine will be needed. It is however usual that chlorine should be added in the range of 1–5 mg/litre. The amount of the 1% chlorine solution described above needed to achieve this range of chlorination are shown below.

Desired

Table 2 – Quantity of 1% Chlorine Solution to add for Different Chlorination Level 1,000l 2,000l 5,000l 6,000l 8,000l mg/l tank tank tank tank tank 1 0.1 l 0.2 l 0.5 l 0.6 l 0.8l 2 0.2 l 0.4 l 1.0 l 1.2 l 1.6 l 3 0.3 l 0.6 l 1.5 l 1.8 l 2.4 l 4 0.4 l 0.8 l 2.0 l 2.4 l 3.2 l 5 0.5 l 1.0 l 2.5 l 3.0 l 4.0 l Levels

This chlorine should be allowed to run through the pipes so that they are also disinfected and then left to stand for at least 30 minutes as this contact time is necessary for it to kill all of the pathogens. Chlorine evaporates from a free water surface so water that is left in the tank will gradually reduce in chlorine content.