How much drop in water level is acceptable? We just turned on our waterfall and there may be a bit of splashing..but it seems to have dropped about an inch. I'm still monitoring it, but had a question...the pond is probably about 1500-2000 gallons and has 4 4in koi/shubukin, 6 tadpoles, and 4 snails... (just bought them all!) and put some plants in as well (lilies, pekering?, some grass, and something else sorry forgot the names). How long can we turn the pump/waterfall off for since it's now inhabited? So that we can see if it's the splash out or if there's an actual leak.