These products all appear here because they are meant to work in an integrated manner, firstly Supa Chlor apart from it's other actions will remove Hydrated Lime from Town Water. When Hydrated Lime comes into contact with CO2 it forms an insoluble precipitate of Calcium Carbonate. In the process of removing this Supa Chlor replaces it with a utilisable phosphate, not a Super Phosphate which is detrimental. then the Blocks, both kinds replace the missing carbon (which Lime removes in Town Water) in stored Rainwater and Town Water. This is done with Dolomite Lime and Glutaraldehyde, because of the way these blocks suspend these Macro Fertilisers they will not cloud water and can be Buried in the substrate or sat on top and avoid the need to be feed into substrate tubes.