Pemburu, I agree with Sissy, wander with your thoughts all you want on this forum, and this thread! We all do, it's the fun of things. I had to read 3 pages of this thread to catch up! LOL I uses peroxide, full strength, last spring to try to get rid of string algae along the edge of my koi pond. It was growing a LOT every day, maybe 6-10" worth. I poured a little just above it (it was growing on the edge, about 4-6" down) and it did kill it. The down side of how I did it, though, was that the peroxide in the water also affected the plants in my water bog, which didn't grow as well early, although they recouperated. AND, my water went very murky. Not green, but brown murky, and stayed that way for over a month! So, I would not suggest doing how I did it. Just be patient, things will cycle and soon get rid of the algae. I will try to follow my own suggestions come spring when my algae starts up again. I usually try to remove it by hand in the bogs and along the edge of the pond. Sissy's way is the best way, treat the filter material with peroxide after rinsing, then put back in. When she says to turn off your pumps, she's I think talking about a waterfall or edge that will then become dry, where the algae is growing. I am going to try that on my waterfall this year, as I had lots of string algae on the rocks there, too. That would work just fine, let the sun help kill it, then turn on the water to rinse rocks off. But, best to use a filter basket of some type to catch the stuff that rinses off the rocks before it gets to the pond. I just suspend or hand a basket for the water to filter through before falling into the pond for a short time.
It's sunny here, not going to be much over freezing, but I'll take it with sunshine. Tomorrow, in the 40's!