my Zen Water Garden and Koi Pond

[Delphinus]

I hear you on the digging Kien. I don't think I'll ever put a pond in at my place as I remember every single minute of digging the post holes for the fence the tree holes.. I'm right over top of some rather interesting glacial sill, which is probably more rock than clay but definitely the right amount of both to make digging very difficult. For the fence, I ran out of steam for the post holes with only two terminal holes left, I hired a bobcat to do the two holes and he broke his auger. He tells me afterwards "I am soooo raising my minimum price for any of your neighbours who hire me."

Anyhow so how do you battle algae in these things?

What's a water change like? Do you pump the outgoing water onto the grass, or what do you do with it? Can you get in trouble if you just pump it into a swail or a storm sewer?