I hit up Lowes today in an attempt to snag some bog plants... and was sorely disappointed. Nothing at all suitable to grow in the water. However I did run across some other plants to start hiding the filter barrels.
The red plants to the left are full-shade plants, which is great because on this side everything is shaded by both the large locust tree and the pine tree (and the filters themselves) -- of course I managed to take the picture in the 5 minute period of day that any sun gets through the trees. They will grow about 24" tall, so should do a great job of covering the filter and some of the fence.
Behind the large red rock and the post, I planted a clematis with white/pink flowers. Once it starts growing out, I'll train the vines around the wooden post and up around the waterfall...
Directly behind the waterfall, in the 3" strip of dirt that is still exposed, I planted a honeysuckle that was in that area when the old pond was here. It has been climbing up the fence over the past year, and with the waterfall now complete, I draped some of the longer vines out across the gravel bed. In my old pond, I had a honeysuckle which used to grow out into the water and float. It liked the pond so much that the floating parts would actually stay green all Winter, despite the occasional hard freeze. This one is going to be trained over to the right side of the waterfall, where it will cover the wood post on that side.
To finish it off, I pulled some of the hyacinths out of the pond and put them back up in the barrels again (not shown in the picture). It shouldn't take them long to really pack in, and they do a great job of dressing up that space (and hiding the plumbing).
I think I'm pretty much set for next year's growing season