I used to use Double clean in my tank sometimes,had pumps go after just 3 months use,bought a Flo Jo pump Jan 2010,and since then have only used fib and fab in the tank,this pump is now over a year old,and anyone on here will know the amount of trouble I had with pumps,touch wood it will last another year,have a spare one as a backup,just in case,and I have also touched wood,wish I could say the same for my heat and run,that has started to leak from the bottom connection,have made some repairs,but it won`t be long before it goes,then looking at around £600,won`t be getting a Prochem one again,learnt my lesson there