About 3 years ago we built a 70x70 dug out pond. The sides are pretty steep (2:1) and the soil is clay. The only water source is rainwater from the building roof, which keeps the pond full, so there should be no external nutrients coming in the water.
This year, for the first time, we’re getting a decent amount of FA. I never had any before, so I’m trying to figure out what changed. One change, for the first time I’ve noticed some rushes growing around the edges, so maybe it just took a few years for things to start to grow. A second change, in the previous years I ran my aeration 24/7, but this year I put it on a timer to save electricity. It turns on at 8 am and turns off at 6 pm.
I’ve also noticed that the visibility is quite a bit higher this year, perhaps 6 feet vs maybe 3 feet in previous years. I’m wondering how much the FA this year is “just the pond getting older”. Another hypothesis is that perhaps the 24/7 aeration was stirring up the clay which was blocking out the light and preventing FA.
For now I’ve added some Dye, and today I put the aeration back on 24/7. Going forward I’m wondering if there is a solution that doesn’t involve due. One option is to just go back to 24/7 aeration. Another though maybe I should switch the aeration schedule to run at night, so that the water reaches maximum turbidity just as the sun is coming up, with the turbidity lasting during daylight hours.
What do you all think?
