Thanks Bullfrog. I bought some white ant powder. Yesterday however they had all gone on vacation , I think the spray must have got rid of them. I still did the rounds with the powder, Belt and braces what. My pool repair was also 400 hundred Pat plus a pair of skimmers and the price of the pipe.We did not use a pool shop. ;) There was a fair amount of digging and he also fitted a non return valve. Anyway this year no green water and more important no water loss.   

This work/expense can all be prevented by not putting the pool tablets in the skimmer basket (s)

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