Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Run aeration 24/7 for FA control?

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?

A day or two trial run of 24/7 air should tell you if you can increase turbidity with air alone. I suggest doing this when you can check it every few hours with a secchi disk (or similar) to monitor the aeration affects on clarity. You may find that the air creates a fair amount of turbidity within the first few hours. If this would be the case, I would start the air that "few hours" of time prior to sun-up and let it continue to muddy up the waters for the duration of the day (turbidity peeking around mid to late afternoon).

My gut tells me that the 6' of clarity is the real culpret. FA (or simialr algae) can grow in a 5 gallon bucket freshly filled with tap water within a week or so...sun, water, & a trace of nutrients and FA is at home.

Aeration experimentation is your first cheap option and now is the time to do it before the FA gets too far out ahead of you. I am actually trying to go the other direction...My Pond has about 12" of visibility and I need to find an aertation schedule that allows more settling to get closer to 2-3 feet of visibility.

That’s helpful Quarter Acre, thank you. I’ve added some dye so that either way I am blocking the light until we learn more.

That’s an interesting idea to monitor “peak turbidity”. I am also wondering how long turbidity takes to “settle out” once the air is turned off. I will aim to run some experiments and see what happens, although it might be a bit challenging with the dye now in.

One hypothesis is that because I was running the air from 8 am to 6 pm, the turbidity basically had the longest possible time to settle out before the sun came up. I’m wondering if I switch the schedule around, so the aeration runs all night, so that the turbidity is maximum when the sun comes up. Then hopefully I can turn the compressor off for 12 hours, but the turbidity will stay strong enough to block the sun for that time.

Any thoughts on how long turbidity in a clay pond might take to settle out?

I am also wondering if the compressor is a “red herring”, and it is actually just that the pond is another year older. We didn’t have any rushes growing around the edges last year either.