alright people this is a little tutorial i'm putting together to show how to easily build an airlift for brewing aerated compost tea (ACT).
if you wanna learn about compost tea and/or compost tea brewing systems, i suggest you check out microbeorganics.com. after reading through that site and the sticky: tea article thread in the organic soil forum, i designed this simple system.
first, i decided the airlift style brewer had several advantages, most notably, breaking the water's surface tension. you can read the details on microbeorganics.com, but basically it increases the amount of dissolved oxygen in the water, which is the aim in an ACT system. another good reason is that the vortex and the microbulator, two of the cooler commercially available systems, both use airlifts to drive their brewers.
the great thing about this is that it's entirely scalable. i'm making one for a two gallon container, because that's enough for my small garden. if you want to brew larger batches, you'll want a higher flow rate, so you'll need something stronger than any of the petco aquarium pumps. check microbeorganics.com for a comprehensive guide for selecting the right air pump for your system.
the materials are cheap and simple. the ten dollar cost does not include an air pump by the way. i had a petco "60+ gal tank" aquarium pump [5 watt], and that seems to work okay for my two gallon brews. for the pipe i used 1 1/4" pvc. you should make sure your pipe is long enough to reach near (but not sitting on) the bottom. you'll need a 180* turn, so you can use two elbows, or get a "p-trap" set like i'm using. it's for kitchen sinks, and has the advantage of an adjustable joint with a silicone o-ring that makes cleaning really easy. you'll also need fasteners like rubber bands and velcro, or whatever you've got.
one assemble the p-trap. two bundle the air hose from the pump together and loop the bottom 8 - 12", securing it with a rubber band 1.5 - 2" from the ends.
three fasten the loop near the bottom of your pipe and the hose once or twice more up the length of the pipe.
four slip the ends of the air tubes inside the end of the pipe. use the tension from the rubber band to pinch the edge of the pipe so the air tubes will stay in place. you want to get the ends of the tubes as close to the bottom of the pipe as possible while staying securely inside.
that's it! now rig up a way to secure it in your bucket, fill up to 2-3" under your spout, and mix up your tea!
i made a brace. i took an extra length of pvc and cut a slit in either end. the slits fit over the sides of my bucket. i used heavy duty velcro to fasten the airlift to the brace.
this brewer is designed for use without a bag. just add your compost directly to the water. edit: the term is free suspention
for your reference, here's the basic recipe as perscribed by microbeman in the sticky: tea article.
happy brewing! stay green!
HB
EDIT: I'VE UPDATED MY DESIGN. TWO AIR PUMPS. DRILLED HOLES AT THE BOTTOM OF THE LIFT TO HOLD LINES, CUT OUTS BETWEEN AIR HOLES TO ALLOW WATER IN ABOVE THE BUBBLES.
if you wanna learn about compost tea and/or compost tea brewing systems, i suggest you check out microbeorganics.com. after reading through that site and the sticky: tea article thread in the organic soil forum, i designed this simple system.
first, i decided the airlift style brewer had several advantages, most notably, breaking the water's surface tension. you can read the details on microbeorganics.com, but basically it increases the amount of dissolved oxygen in the water, which is the aim in an ACT system. another good reason is that the vortex and the microbulator, two of the cooler commercially available systems, both use airlifts to drive their brewers.
the great thing about this is that it's entirely scalable. i'm making one for a two gallon container, because that's enough for my small garden. if you want to brew larger batches, you'll want a higher flow rate, so you'll need something stronger than any of the petco aquarium pumps. check microbeorganics.com for a comprehensive guide for selecting the right air pump for your system.
the materials are cheap and simple. the ten dollar cost does not include an air pump by the way. i had a petco "60+ gal tank" aquarium pump [5 watt], and that seems to work okay for my two gallon brews. for the pipe i used 1 1/4" pvc. you should make sure your pipe is long enough to reach near (but not sitting on) the bottom. you'll need a 180* turn, so you can use two elbows, or get a "p-trap" set like i'm using. it's for kitchen sinks, and has the advantage of an adjustable joint with a silicone o-ring that makes cleaning really easy. you'll also need fasteners like rubber bands and velcro, or whatever you've got.
one assemble the p-trap. two bundle the air hose from the pump together and loop the bottom 8 - 12", securing it with a rubber band 1.5 - 2" from the ends.
three fasten the loop near the bottom of your pipe and the hose once or twice more up the length of the pipe.
four slip the ends of the air tubes inside the end of the pipe. use the tension from the rubber band to pinch the edge of the pipe so the air tubes will stay in place. you want to get the ends of the tubes as close to the bottom of the pipe as possible while staying securely inside.
that's it! now rig up a way to secure it in your bucket, fill up to 2-3" under your spout, and mix up your tea!
i made a brace. i took an extra length of pvc and cut a slit in either end. the slits fit over the sides of my bucket. i used heavy duty velcro to fasten the airlift to the brace.
this brewer is designed for use without a bag. just add your compost directly to the water. edit: the term is free suspention
for your reference, here's the basic recipe as perscribed by microbeman in the sticky: tea article.
happy brewing! stay green!
HB
EDIT: I'VE UPDATED MY DESIGN. TWO AIR PUMPS. DRILLED HOLES AT THE BOTTOM OF THE LIFT TO HOLD LINES, CUT OUTS BETWEEN AIR HOLES TO ALLOW WATER IN ABOVE THE BUBBLES.
upgrade!
thanks to rip van weed for the clever idea. it really improves the flow (and hopefully circulation)!
plus i fashioned a much better brace to keep the air lift upright.
.....
