Thanks again Mike and I don't think you "Go-on to much" but then I am biased. As for the Blackworms, Never seen or heard of them before now so unless anyone on the List in the UK knows where they can be obtained, I'll have to forego the pleasure and my wife's annoyance. Since I spend a lot of time and effort reducing the hardness of my water anyway, I'll try reducing the pH in some of my tanks down to 5 and see if it will induce the "little bugger's" to spawn. I'll let you know. As for Ken's suggestion, Thanks but when you work out the cost of the unit and the 2-3 weekly replacement of the unit, ($82.50 for the De-ioniser and $33.00 every 200gals ) it would work out more expensive than the R/O unit within a very short period of time, anyway how does someone in Hawaii know about Animal House. Stuart Greenley Kingston upon Hull, England stuart@snoopers.karoo.co.uk