Gidday Bob,
I didn't move over to Aussie Land till '88.
I understand your comment re contributing to the economy.
When I pulled in to Subic Bay on HMS Albion in '71, it was obvious Olongopo's economy was run by income from the US Navy.
Likewise Wanchi (Hong Kong) came alive when the Brit Far East Fleet was in, and it positively boomed when the 7th Fleet made an appearance. Never seen so many worn out bar girls
Oh to be young again.
TB - re your problem. Ask your local Nurserymans Assn what causes fish kills, or ask your local Ag Chemical Company (the ones that sell fertilizers/insecticides/fungicides etc). They should have a specialist to advise you. Should cost very little: be 100% effective: have no lasting effects.
Cheers
Phillip