It shouldn't be a problem, unless possibly you're starting with completely sterile soil largely devoid of organic matter.

There should be well more microbes naturally present in your garden than any you will add by compost tea. Chloramine is present in municipal waters in very small amounts, and it will readily decompose when it contacts about anything organic in the soil, so when you irrigate with chloraminated water the residual chloramine is rapidly destroyed. The microbes in your soil and compost will hardly be affected in number, and if your soil is reasonably healthy from an organic view any loss will be rapidly replaced. I use treated municipal water for everything - irrigation, wetting compost, etc. - and my soil is teaming with life and my compost has never shown any sign of being affected.

Still, many have concerns, and if you're in that group an in-line carbon filter system will largely eliminate the residual chloramine. Just change the filter periodically based upon the manufacturer's rated capacity and your usage. One very simple screw-on filter can be added for about $40, and it's rated for 10,000 gallons.

using the water that has been filtered for a reef tank means either reverse osmosis or more likely deionized water. That has to be the most absolutely unnecessarily wasteful use of water I can think of. RO produces 4x the amount of wastewater as filtered water and DI is just pointless. Carbon filtration is all that is necessary and you don't even need to do that in order to make ACT.

But more importantly, why are you making ACT? If the answer is anything other than to make a dilute liquid fertilizer, you might as well just topdress with compost. The act of watering will make your tea in situ and you won't waste electricity on an air pump.

Agree with nil13 on the utility of compost tea.

The benefits of compost tea are largely anecdotal, advanced by practitioners. Attempts to reproduce the claimed benefits via well controlled research studies have been hit and miss, but mostly miss.

The whole idea behind compost tea is to culture the microorganisms that inhabit compost. My sense has long been that they do their best in their natural environment, not in a typical compost tea medium, and then after supposedly being cultured being sent to live in soil with the subsequent abrupt environmental change. I've long thought that the best use of compost is to put it into or on top of soil.

Before you decide to go through the process and invest the effort and resources, I encourage to carefully go through the presentation from Kentucky State University.

Here is a link that might be useful: Compost Tea - Kentucky State University

I thought I was reading that you need to use water that is free of both chlorine and chloramine, it would kill off any microbs that you are trying to make with compost tea.

I'll be using a 20 gallon trash can to make the tea. If I put in 4 or more inches of compost and the water with molasses and aerate, wouldn't that possibly make the same amount of microbes as several large bags of compost?

It seems like Harvard is seeing benefits from using ACT: http://youtu.be/WlcX2WpnQWI

This post was edited by NickRose on Wed, Jul 31, 13 at 17:22

Chloramine in water is readily decomposed by natural organic matter in the water - any oxidizable organic matter. One very well known advocate for the benefits of compost tea teaches treating municipal chloraminated water with 1 teaspoon of humic acid per 100 gals of water to destroy any residual chloramine (and that is likely plenty of overkill). That amounts to ~ 50 mg of humic acid per gallon of water treated. If the compost you will be using is ~ 50% moisture, then 1 tablespoon will represent ~ 8 grams of organic material. If even only one tenth of that were oxidizable (and it is mostly oxidizable OM) that 1 tablespoon would be well more than enough to eliminate the chloramine in 15 gals of water pretty easily.

First, what grows in the tea will probably not be representative of the diversity and relative amounts of what's in the compost - that has been established from several studies. Second, the microbial population that you develop in a culture medium doesn't translate to the viability of whatever is cultured in the soil once transferred. When you apply the tea to soil, the nutrient broth is very quickly lost. The microorganisms need a food source to survive and develop. So what will they eat now?

If you want to increase the microbial population density in your soil provide the soil with a food source for the microbes, meaning organic matter they can digest. They will optimally populate the soil based upon the organic matter, pH, oxygen level, moisture, etc. One of the easiest, fastest and most conservative ways to do that is by adding compost to the soil.

As for results, I will stick to well controlled studies. As I noted earlier, in controlled studies results have been hit and miss, but with ACT mostly miss.

What if I did a combination of compost mixed into the dirt and as mulch and then add the compost tea? I guess it just comes down to experiment and see what works. I mean really that is one part of being a gardener. Take my experiment with seeds from a grocery tomato. Most of the plants are 5'8" and have several sets of tomatoes.

Nick - your resources would really be better utilized if you put all of the compost in the soil, and then kept it properly irrigated. As best I can see, there is no clear benefit that comes from developing a liquid culture from compost and applying it to soil relative to just adding the compost to the soil. But, there are a number of potential hazards (see the presentation linked above). There is also the resource consumption without benefit, but for the average gardener it is such a small bit that it is generally missed and forgotten.

As for your seed experiment, from what I've seen most market tomatoes are modern hybrids. It will be interesting to see what your plants yield. A good breeder with knowledge of the market cultivar that the seeds came from could probably tell you, in advance, what you'll be getting. I have lots of tomato volunteers in my garden from seeds that came from fallen fruit and those that, after passing through the kitchen, lived through composting I know, however, that they most likely won't be true to the hybrids from which they came (all six varieties of the tomatoes I grow are hybrids), so they get eliminated as weeds.

IIRC, Harvard uses ACT on lawns where compost would be unsightly. Like I said, it is a dilute organic fertilizer, so using it as an organic lawn fert makes sense.

If what you want is a dilute organic fertilizer, there is no need to go through the fermentation process, and adding molasses, kelp, fish stuff, etc. Just take the compost and stir it into water, let is sit a few hours with an occasional stir, then apply the extract to whatever.

The real utility of a compost extract is exactly what nil3 pointed out - it allows for the use of the nutrients extracted from compost AND any water soluble organic materials with the attendant microbial flora/fauna to areas, like public use turf lawns, where compost can't be added to the soil directly, or top dressing with compost would be either impractical or troublesome.

This post was edited by TXEB on Thu, Aug 1, 13 at 12:24

Organic fertilizer is what I was going to use it as. Since I guess I wont go with ACT I wont use a 20 gallon trash can. So how much will a 5 gallon bucket cover?

TX, I think that while the fermentation process is unnecessary, the act of aeration is really just functioning as a stirring mechanism to keep more compost suspended in solution thus increasing the surface area available for extraction.

My choices for water in brewing compost tea.

1) rain water
2) tap water aerated for three days or more outside

Your water supplier can tell you if it is currently using free chlorine or chloramine. Many will switch back and forth during the year.

nil - while the aeration no doubt provides agitation, it is actually essential for the growth of aerobic microorganisms -- think about biological oxygen demand. I have no doubt that, done properly, the liquid culture is absolutely teaming with anything microbial that was added - not just from the compost, but from the nutrient additions (they are hardly sterile) and the air itself. In the absence of aeration a very different microbial development will take place, dominated by anaerobes.

Nick - not sure what you're asking -- 5 gal's of what, covering I'm not sure what?

TXEB- 5 gallons of the compost and water you talked about. I would like to use it around the whole garden. I have a 35' row of rose bushes, 6 tomato plants in the ground, watermelons, lemon tree, 4'x6' of Bell Peppers, etc.

Nick, why not just add compost to the beds? It would be much easier and add more nutrients than can be extracted.

TX, I understand the process. I'm just saying that aeration can be used in place of stirring. It's sort of a poor mans mag stirrer.

I'm going to have to do some experiments. With most of the garden I will just put down the compost itself. The experiment will be with the Bell peppers I'm growing. Since I have two rows of Bell peppers, I will do one with with just a dressing of compost and the other side with aerated compost tea.

Nick - a good mix for compost extraction would be 5-10% by weight of compost in water. Five gal. of proper compost should weigh in about 25 lbs, water is 8.3 lbs/gal, so at 10% compost by weight you would shoot for 250 lbs net, which would be 225 lbs of water, which is about 27 gal's of water. For 5% just double the water.

That said, I'm with nil - the better application would be to just portion out the compost around the plants - cultivate it into the top couple of inches of soil where you can, use it as a mulch where you can't - and then irrigate normally. It will provide lasting benefits that way, and you'll get everything out of it.

A couple of questions - are you planning on straining the extract to remove the solids before applying the liquid? If so, what do you plan to do with the solids? If not, why complicate the application with a slurry?

This post was edited by TXEB on Thu, Aug 1, 13 at 20:41

I was going to strain the extract and the solids would be used as mulch.

So I'm sure you saw this coming - why not just apply the compost as a mulch then irrigate over top?

I had that one coming. Like I said I'll amend in the compost with the whole garden and do the experiment with the bell peppers of using compost tea with one half and using regular compost on the other. If I see a difference with compost tea then I will go that direction but if I don't which from this thread I wont, then I will just amend in the compost throughout the year.

Cool!

Nick - please let us know how your tea vs. compost experiment works. Maybe we'll all learn something.

I will keep you guys updated. You can also see my tomato experiment at the link. The tallest tomato is 79".

http://forums2.gardenweb.com/forums/load/cornucop/msg0522493931728.html

Since I first read about compost tea I wondered the benefits of it over working it into the soil of the garden. Now I see there isn't much if any in that application.

Now in potted house plants perhaps.