“Swimming pools have crept across the affluent suburbs so that, from the air, these ponds now resemble a virulent aquamarine rash on the urban fringe. The colour is artificial, like that blue dye that imitates an ocean wave obediently crashing down the toilet bowls of the over-fastidious. Chemicals used to purify the water are biocides, and we are biological organisms; if fish can’t live in our pools, we should also keep our bodies out of the water. When chlorine isn’t being used as a war gas, it is being dumped into our drinking, bathing and swimming water, where it forms carcinogenic chloroform.
Innovative pool designers now filter natural pools below a base pebble bed, using the pebbles as algal/bacterial cleaners, then cycle it through a reed-bed to remove excess nutrients before cascading it back, freshly oxygenated, into the pool. Such pools can be delightful systems with tame fish, crayfish, rock ledges, over-arching ferns, and great good health.”