Don't overtreat your ponds.
Clean water adds beauty to landscaping.
Resist the temptation to overtreat weeds and algae if you've already allowed them to take over a pond. Overtreating will do just that, killing everything - including fish. Even though most of the treatments we sell are safe for fish, if you kill off all the vegetation, you'll end up depleting the oxygen supply. And that is what will kill the fish. Of course, the best advice is to catch pond weed and algae problems early.