Originally Posted by
kimini
Our latest pond is just over two years old. During its two-year "seasoning", we had a real issue with string algae, and even posted a few pictures of here. It was especially bad because it would block the bottom drains even with their 3/4" gap, and produce soccer-ball size mounds of algae in the RDF. H2O2 would beat it back for a while, but it would always come back. Water chemistry is great other than high (40+) nitrate due to 5% water changes per week, but the fish appear healthy and active.
Now for the change: Starting about 3 months ago, it gradually started going away on its own, and eventually disappeared. I wasn't too surprised by that, given how each pond is different and has its own personality. What was a bit surprising is that the algae reduction just kept right on going, to the point that there's not much anywhere, even on the walls. I should also note that while UV is used, it obviously doesn't affect the algae that stays in the pond.
There have been zero changes in feeding schedule, water change amount, no rain, and no fish have been added or removed. Perhaps the miracles claimed of shower filters really do happen, but as said above, nitrate remains high, so miracles seem doubtful. I want to be happy about this, but it's the unknown that makes it a bit concerning. As said above, the fish are healthy, hungry, and active, so it's kind of a head-scratcher. Unlike some pond owners, I won't take responsibility for the improvement in clarity, and maybe it's just another mystery which is algae.