Increasing Water "Churn" in Self-Watering Containers

rnewste · August 30, 2009

I once thought is was a "good thing" to have a large water reservoir in the design of a Self-Watering container, but I now take the extreme opposite view today.

What I have found is that water held in a large reservoir can stagnate, become an easier home for mosquito breeding, and buildup of algae growth on the side-walls that are constantly under water:

The availability of the ingenious Automated Watering System from the EarthBox Company now permits "always on" level control so that you can precisely control the water depth to an eighth of an inch accuracy. The passive system is easily adaptable to homemade SWC units.

On the left, is the "stock" AWS unit as it comes from the EarthBox folks. It is quite simple to lengthen the sensor tube from the original 10", to what I use in the EarthTainer of 11.5". This keeps the water level in the 'Tainer to about 3.5" at all times.

But in an effort to minimize algae growth, etc. and more importantly, to have the reservoir water as "fresh" as possible at all times, I wanted to have kind of F.I.F.O (First-In-First-Out) system where water would be constantly "churning" at the very bottom of the 'Tainer. So what I've now done is to lengthen the sensor tube to 14" thus holding the water level at a constant 1".

Since the two tomato plants will consume one to two gallons per day in mid-season, water should cycle through the 'Tainer every 24 hours or so. I realize that as a liquid, I won't get 100% F.I.F.O. but it should provide fresher water to the plants with this approach. Of course, this significantly increases the frequency of watering that one would have to do manually, and the AWS makes this a "don't care" event.

The AWS unit cost on a per plant basis works out to be under $5.00 today (They are having a Sale on currently at the EarthBox site). I figure a 10 year service life, so at under 50 cents per year cost per plant, this system is a real bargain for the time savings, and peace of mind when away on vacation.

I suppose if one had a 'Tainer on a perfectly level surface, you could experiment with keeping the water level at one-quarter inch at all times using a 14.75" sensor tube - - but I'll stick with the constant one inch water level for now.

Ray

August 30, 2009	#1
rnewste Tomatovillian™ Join Date: Apr 2007 Location: Campbell, CA Posts: 4,064	Increasing Water "Churn" in Self-Watering Containers I once thought is was a "good thing" to have a large water reservoir in the design of a Self-Watering container, but I now take the extreme opposite view today. What I have found is that water held in a large reservoir can stagnate, become an easier home for mosquito breeding, and buildup of algae growth on the side-walls that are constantly under water: The availability of the ingenious Automated Watering System from the EarthBox Company now permits "always on" level control so that you can precisely control the water depth to an eighth of an inch accuracy. The passive system is easily adaptable to homemade SWC units. On the left, is the "stock" AWS unit as it comes from the EarthBox folks. It is quite simple to lengthen the sensor tube from the original 10", to what I use in the EarthTainer of 11.5". This keeps the water level in the 'Tainer to about 3.5" at all times. But in an effort to minimize algae growth, etc. and more importantly, to have the reservoir water as "fresh" as possible at all times, I wanted to have kind of F.I.F.O (First-In-First-Out) system where water would be constantly "churning" at the very bottom of the 'Tainer. So what I've now done is to lengthen the sensor tube to 14" thus holding the water level at a constant 1". Since the two tomato plants will consume one to two gallons per day in mid-season, water should cycle through the 'Tainer every 24 hours or so. I realize that as a liquid, I won't get 100% F.I.F.O. but it should provide fresher water to the plants with this approach. Of course, this significantly increases the frequency of watering that one would have to do manually, and the AWS makes this a "don't care" event. The AWS unit cost on a per plant basis works out to be under $5.00 today (They are having a Sale on currently at the EarthBox site). I figure a 10 year service life, so at under 50 cents per year cost per plant, this system is a real bargain for the time savings, and peace of mind when away on vacation. I suppose if one had a 'Tainer on a perfectly level surface, you could experiment with keeping the water level at one-quarter inch at all times using a 14.75" sensor tube - - but I'll stick with the constant one inch water level for now. Ray