I've been investigating everything to do with azolla, since it seems to be the most promising nitrogen producer available to me. It makes good fish and chicken food.
The water beneath a solid mat of azolla, is low in nutrients, low in phytoplankton and floating algae and more clear than in ponds where the water is exposed to sunlight. Mosquito larvae don't like to live under azolla.
I often shower in water from natural sources. This seems like a much cleaner source of water, than some I have used.
Utilization would be dead simple. Pump the water into a batch solar collector, let it heat and use it at the end of the day.
The shower could be built on the edge of an artificial wetland that slopes toward the same pond. Azolla processes nutrients very quickly, so it wouldn't need to be a very big pond. The whole thing, including the shower and wetland could probably be as little as 100 square feet.
Azolla would need to be removed, whenever it forms a thick mat where lower plants don't get much light. It can be fed to the chickens or composted. This keeps nutrients constantly moving out of the bathing pond.
The limiting factor for azolla growth is available phosphorus. It grows exponentially, in phosphorus rich water. When phosphorus runs low, it turns a crimson color and grows more slowly. This color change, can be used as a barometer of nutrient load. Whenever the whole plant or portions of it are crimson, this means that prosperous is running low. Someone farming azolla to feed to their tilapia, would immediately add phosphorus. But we're not looking to maximize azolla production. It can be kept alive for a long time, with minimal nutrients added. If it stays green all the time, then you know that the pond is not large enough to absorb the input.
I haven't done this yet. The idea is almost as new to me as it is to you.
Do any of you know of this being done before? Other thoughts?
That's all I've got. I hope it proves to be this simple in application.
I know nothing about azolla but I do know that a lot of soaps, including natural/organic ones, are high in phosphorous so you may have struck on a real perfect system here.
Location: Victoria British Columbia-Canada
posted 3 years ago
Yes, I actually hope to find organic soaps, that don't make any attempt to limit the amount of phosphorus. If I overload the system, some of the shower water could be dumped into the much larger pond that is meant to produce chicken feed.
Seems like a nice tidy loop.
I currently just let shower water run into the soil. It's mostly rock flour, with trees growing on it. They can absorb far more nutrients than I have ever given them.
Water is drawn from the pond and the effluent from the shower, runs through a little river of cattails and Iris, and then runs into same pond.
Alternatively, when the water is really warm, I could see just getting into the pond and soaping up right there. With no outlet, there's no danger of getting soap into the river or anywhere else. If the system became overloaded, some of this water could be used under the trees and the pond refilled from the much larger one that is lower in nutrients.
Water fowl would need to be kept out of this. They carry swimmer's itch.
I have swam and bathed in the same small body of water, several times in a row, with no attempt to control water quality. This would return the water through a long skinny filter of gravel with plants growing in it. I'm thinking something 2 ft wide and 10 ft long. Maybe 18 inches deep. Perhaps not perfect, but much better than what I've used in the past.
Pre filtered water, would then have nutrients sucked from it in the azolla pond.
I suppose any functioning system could be tested by adding nutrient in various ways, until overload is reached. If a system like this were built for a town, I'm sure there would be testing. If I build something like this for myself, I will see if it makes me itchy or causes some other obvious problem. Not terribly scientific.
Do you pee on your compost? Does this tiny ad?
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