Well, I left on holidays last Wednesday morning, and just got back last night. Did a 5-10% water change before I left (it takes FOREVER to drain off just a couple inches, lol).
It was hot and sunny the whole time I was gone, and I figured I'd be coming home to pea soup.
Nope!
The pond looks GREAT. It's far from clear, but much, much better. You can easily see down a foot now. Fish look fat and happy. My one canna is blooming, and the other two are growing like crazy. Lily bloomed while I was gone, and has another bud that should break the surface in a couple of days (this will be the 4th flower since I got it!). Cattails are all doing great. My green taro is still struggling, but my black magic taro is doing fabulous. Parrot feather is taking over one whole corner of the pond - yay for shade and filtration!
I talked to an "expert" in a pond shop on the Island while I was away. Her advice was just to leave it be. She said that next year, if it greens up again, I may want to add a UV filter.
For filtration, right now, all I have is a Laguna Power Flo Max, hooked up to my Pondmaster 2100gph pump. However, over the next few weeks I'll be building the upper pond which will include a 200g pond, bog garden, and waterfall. That should include the filtration significantly (the bog garden will). If things seem inadequate after that, I'll build a skippy filter. However, I think using the Power Flo Max as a pre-filter, and then having everything go through the bog garden and the upper pond as a settling pond (chock full of hyacinth!) should be sufficient.
The only problem I'm having with the pond now is aphids. I noticed them a couple weeks before I left, and was dealing with them by dunking and rubbing them off. They were almost gone. However, while I was away, I didn't have the house/pet/kid sitter follow up on that, and they're back worse than ever. I'm going to hit the garden center today and see if I can buy some ladybugs. I'm also going to use a recipe for a fish/plant safe pesticide that I found online (it's basically cooking oil and water).
Wish me luck!