Bullfrog; That is exactly what I've done.
130$ for 15 gal cone with no stand and shipping included.
80$ for Commercial Ecco 5 at my grow store, they have fantastic prices. (you might be able to get away with the Commercial Ecco 1 or 3 according to MM)
tubing cost maybe 10$ (not 100% sure)
PVC cost maybe 20$ (not sure here either)
Hose clamps $1
PVC glue for trouble fittings, 5$ but I already had a bunch.
The stand I built out of spare lumber from a job I was working on. However it took about 2-3 2x4's to build, so less than 10$ for the stand.
Handful of 2 1/2 inch screws. 3-10$
So about 246$ for the brewer, maybe 20 for the stand max. I am pretty sure this would be on the high side if off at all.
$130 for the cone. Why not look at thermoforming a cone of your design? Have a small shop do this, I mean. Very low tech and perfect for lower production runs. I bet you could get production costs to $20.
It sure adds up doesn't it? It is very tough putting together a decent brewer cheap and then trying to make some income. Everybody always says it is just a bunch of pipe, tubing, fittings and a pump. Why is it so expensive? I say you run around and find all those fittings then and put it together yourself.
Hey Scrap,
Pictures would be better fo sho.
Anyway, if I'm following your description right it sound like the problem may be that your lift is not vertical. If your teeing off from the bottom of the tank you must be running part of the lift at an angle less than straight up, won't work, bubbles rise to the upper side of angled pipe and passes all the water.
The lift needs to rise straight up so the water will get trapped on top of bubbles and be pushed straight up.
I fabbed mine like this.
Air diffuser runs on it's own pump. Cut slots in the bottom of the octogon with the thinnest Dremel cutting wheel. Delivers air to the perimeter at the bottom.
Then I fashioned this manifold for the bottom of the lift. Four 1/8" elbows delivering air and cutouts to allow water above the air outlets
It lifts more than 1.5 gpm of water from the bottom of the bucket!
Respect,
Still a work in progress, but I'm getting closer.
I'm using an eco air 3 commercial pump. It is rated at 65 liters per minute, I would not go any smaller for an air lift design as it is barely enough to force the tea up and over.
But just the pump and diffuser in the tank without the air lift return up riser agitates better than the air lift, but i have no way to measure dissolved O2 difference each way.
The tank came with threaded nuts embedded on one side of the tank, so I screwed the tank to the plywood, then U bolted the plywood to the cart.
The bottom pic shows the homemade diffuser. It is simply a piece of pvc that has been plugged and jammed into the female end of the barbed fitting, and is inside of the return up-riser. It has tiny holes drilled on an angle to force the air up......scrappy
Diffuser:
Thanks Heady blunts, as you can see, I borrowed from other posters previous designs and MM's web page. Thanks to all.
Actually it does run with only two gallons of tea in it, although that would close to the minimum, at one gallon the return line drips and spits a little, two gallons maintains a flow, and the flow increases as the volume goes up. I only tested up to 5 gallons because my outside water is still not hooked up yet because we still are getting below freezing temps in my neck of the woods. So 5 gallons is all I hauled for this test. I ran it 24 hours with two gallons of tea, it did foam up nice, but I doubt the tea was very biologically active due to our low temps. I poured it on my compost pile. I did have some build up of mud on the bottom of the tank. The "cone" is more like a pyramid and has a flat spot on the bottom, so that gets a little build up, but I doubt it is enough to worry about. When set up as an air dump, there is not much agitation, when it is run as a bubbler style, it agitates real well. I wish I had a meter to check the dissolved O2 each way......scrappy
Edit although it's tuff to see in my pics the upriser is reduced from 11/4 to 1 inch. This helped get better flow.