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Post your DIY Aerated Compost Tea Brewer (proprietary brewers will be tolerated)

Microbeman

The Logical Gardener
ICMag Donor
Veteran
where does it say that MM suggests drilled 250 micron holes for the diffuser? also does anyone have any idea on the average bubble diameter that such holes would produce?

I do not suggest this. This arises from the fact that in my bioreactors (brewers) I make diffusers from pipe which I get slotted uniformly at a PVC machine shop. The smallest size they cut is 254 microns = 0.01 inches = 0.254 mm.
 

grow nerd

Active member
Veteran
Is it possible to create a vortex with a bottom drain on a relatively flat-bottomed 55-gal drum/barrel? Does it need to be cone-bottom for an efficient vortex, or would a 2" PVC fitting epoxied in and bottom bowing out slightly from the weight of the water do the trick?
 

grow nerd

Active member
Veteran
I found that a 3/4" PEX pipe softened with a heat gun will fit an EcoPlus Commercial Air 5's outlet snugly, and a 3/4" CL200 PVC pipe will fit an EcoPlus Commercial Air 7 well without heating.



However, I'm wondering if these pumps were rated to be used with tubing that size, and wondering if it won't potentially reduce pressure and make it less effective when used for applications such as lifting a column of water?

I'm planning on heating and bending the pipes instead of using fittings, to provide a smoother bore with less sharp angles.

(Fitting "tubing" over the outlet rather than installing the brass barbed fitting inside was suggested by someone [maybe Microbeman] to increase airflow.)
 

grow nerd

Active member
Veteran
I tried DIY'ing my own cone-bottom container with a 55gal polyethylene drum and a deer feeder cone of the same material. I thought of using epoxy to seal the two but practically speaking it will cost a lot of $$ to fill all the voids, and even then it will likely be an iffy seal without a ton of prep work (cleaning, cutting, and maybe texturing the surfaces).



So far I consider it a fail because getting it in shape to be usable after filling with 40+ gallons of water will cost plenty more time & money, and by the time that I figure in that $40 I've already spent ($20 drum, $20 cone), I could just save the headaches and buy a real-deal cone-bottom tank which I imagine will have decent craigslist resale value, whereas the DIY version will have little to none.

I expected the cone to snugly slip over the drum, and that I could seal it using a single syringe-tube of epoxy. The outside rim of the cone is exactly the same diameter as the narrowest point of the drum, and fitting the cone inside leaves gaps that are too large to fill economically with epoxy.
 

grow nerd

Active member
Veteran
Ok so a practice run with a 5gal brewer for foliars before attempting a 55-100gal brewer.

Finally decided on 1/2" and 3/4" SCH40 PVC to run air.

Warmed up with a heat gun for a snug fit.



Test run, minimal "pinching" on heat-bent PVC without using sand or air pressure. Just gentle bending and water cooling. Spray bottle would have been handy.


I tried hard to find a water bottle without a handle denting perfect round cylinder, but could not. I know they do exist because I've seen them in the past. Doesn't matter, seems to be working good enough.




I expected this 2" x 1 1/2" rubber fitting would fit the water bottle, but the 2" side was too big. Got some 2" PVC, heated and fit around the water bottle's mouth for an air-tight fit without glue. Will seal with epoxy at the seams just in case. On my next trip to the store I'll replace the rubber fitting with a 2" to 1 1/2" reducer PVC fitting.





Most joints are cemented. I'm not sure if that was a mistake; I thought such a small system would be relatively easy to clean out with pressured water and bleach/soap, and figured solid leak-free joints outweigh being able to take it apart for thorough scrubbing.
 

grow nerd

Active member
Veteran
Mentally went back and forth on pipe/tubing diameter & type between the air pump and air lift column.



You can see I'm really trying to avoid using the included barbed fittings that will restrict the output hole size down even further.



Although I'm wondering if it's not better off using smaller diameter tubing in "pressure" applications like this? I understand that a larger diameter pipe will result in a larger volume of air potentially being movable but with a larger diameter I wonder if such a low-pressure (5.x psi) pump will waste a lot of effort "compressing" the air in the expanded volumes of a larger diameter pipe, and the reduced output pressure at the brewer column may result in a smaller volume of air being pumped in practice. Just a theory, not sure how it really works.

I can't quite say exactly as I did the test runs on separate days, but seems that the EcoPlus Commercial Air 5 with a 3/8" ID tubing @ ~6ft creates a stronger vortex than 1/2" ID pipe with prototype bends, probably longer than 6ft length. Some things were different, such as how high I was at the time of testing, level of light, and angle of splash.

I'll do a "side-by-side" soon when I go get more parts. However, this time I'm mostly going to try to avoid bending PVC myself and use a 1/2" MPT x 1/2" barb fitting to connect 1/2" ID vinyl tubing (non-braided, much cheaper) to compare against the 3/8" ID polyethylene tubing. I consider the DIY PVC bending largely a failure; I imagine that if I had a meter of sorts to quantify, it would show a loss of efficiency due to extra length and imperfect bends, and I'd be better off with tubing or maybe PEX pipe. Probably won't make a huge difference in the end result, but I'd like to know the answer just out of curiosity and future reference.
 
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grow nerd

Active member
Veteran
Not sure whether anyone is even reading this thread, but I'll post anyways.

Here's my first batch of tea going.



Started with plain tap water that has 1ppm of chlorine. Put in a tiny little "bump" of ascorbic acid powder, let it run for a few minutes to de-chlor, then start adding the ingredients. I haven't done too much searching for a basic tea but so far it seems to me like this is roughly an average of many other people's recipes I've seen online.

Per 5-gallon brew, probably about 4.5gal tops, likely 4.25 after losses to splashing and evaporation.

1 cup Buckaroo EWC
1/2 cup General Organics Ancient Forest (humus soil amendment)
45mL Earth Juice Hi-Brix Molasses For Plants
2 Tbsp Down to Earth kelp meal

On my second batch I've added 1 oz of Organic Ag's Pure Protein Dry (PPD, aka DHP).

I did not use a mesh bag, except when draining out to filter for foliar trials. Not sure what mesh size, but sold / tagged by Vermicrop Organics as a compost tea bag.

Right now my brewer is using a 1 1/2" PVC air lift column (with a 1/2" air inlet) but wondering if a smaller (or larger) diameter column might not work better. Anyone care to share experience on this?

A 100gal cone-bottom inductor tank, metal stand and shipping roughly about $500 - $600. Add two EcoPlus Commercial Air 7's (about $100/ea), fittings and brew ingredients and it's easily $1k. A 50ish gallon setup isn't much cheaper, maybe saves $200 - $250 and only slows things down IMO. I imagine you can't use full capacity meaning maybe 40 gallons out of a 50 gallon tank, 85 - 90 gallons out of a 100gal, etc.

Looks like a USB microscope can be had for about $50 - $100 depending on quality and features (and seller!)

I'm wondering if it wouldn't be cheaper / more convenient / more reliable just to get some stuff from AEA & Tanio like all the cool kids are doing.
 
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xmobotx

ecks moe baw teeks
ICMag Donor
Veteran
so far, I can't really quantify differences between tainio & brewing your own. I haven't scoped my tea but, as i got better @ math & following instructions, i got closer to MM's suggested ratios. This made a notice-able difference like, applying my compost tea made for praying leaves & healthy progress compared to no observe-able difference when using an aquarium pump & funny amounts like a handful of compost & a TBS of molasses.

i think the brewer is really valuable even w/ retail-product stuff. it makes a great mixer!
 

Nes

Member
Wow, a lot of awesome designs here!

Here's what I got going right now
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xmobotx

ecks moe baw teeks
ICMag Donor
Veteran
i do 4 gallons & in rough figures, i add 1 cup of compost & 2.5 oz {i use the graduated shot glasses} molasses

sometimes, i may add less than a TBSP of kelp meal ~but, i kinda like just compost & molasses
 

grow nerd

Active member
Veteran
This might be well-known already, but a few drops of neem oil in a 5 gallon brewer killed the foam within seconds. According to Storch Oil (which is a blend of neem & karanja oils along with "minerals", $35/4oz), this does not harm the microbes or fungi.

I find the foaming (often overflowing) quite annoying.
 

maulwurst

Member
hey guys I was thinking of starting a brewer and could it be as simple as a small bucket with a pump and an airstone I only really need ACT on a really small scale.
 

Mikell

Dipshit Know-Nothing
ICMag Donor
Veteran
Yup, though I always recommend looking at Microbemans recommendation for pump size ie. .05-.08 CFM of air per gallon of water.
 

maulwurst

Member
can your pump be to strong? My pump is 240l/h or 0.4l/m or 0.14CFM does that mean I could brew up to two gallons? if I brew lower amounts would it be affected, sorry for spamming this thread for newbie questions.
 

grow nerd

Active member
Veteran
If it's so strong it is causing excessive splashing, it could be too much. Other than that, no.

I have a feeling pressure plays a big role as well, but it's not widely discussed around these parts. Most if not all of these air pumps air capacities are rated on zero back pressure, and depending on the design of the pump the capacity can take a nosedive with some pressure ie generated by sunken air stones, lines or inlets, tubing, fittings or whatever.
 
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