Compost tea spray rig PSI

[ICT Bill]

I have been asking around as I have been traveling about the typical PSI on the spray rig while spraying compost teas. I am not an applicator and do not have a lot of experience with different spray rigs. Some say as high as 200 PSI while others say they never get above 80 PSI

What type pump do you use and what is the typical PSI while applying to lawn and landscape. I understand if you are trying to reach 60 feet into a tree you will have to crank it up, but what is typical for lawn and landscape??

[hunter]

For lawns and shrubbery we use just a 50psi 12volt pump. Don't really need more than that and we cover as much ground spraying at 50psi as we do running at 150 when we are spraying trees.

[Turboguy]

There are a lot of people here who know a lot more than I do about compost tea but I am doing my best to learn all I can. I do know a lot about sprayers.

As far as too little pressure as long as you have enough to pump the CT through the lines and apply it I can't think of a single reason that low pressure would be a problem.

Some of the people here who have worked a lot with it and really paid attention to what was coming out the end seem to feel that about 70 psi is won't cause a problem for the microorganisms but seem to feel around 85 psi you will see a marked decrease in live microorganisms.

To me that all makes sense. I am sure if someone were putting a few hundred psi on me I wouldn't feel too chipper after.

As far as sprayer pumps go most turf sprayers are designed to pump materials that are not alive. I would not even consider a roller pump. Using something unrelated to spraying to illustrate, the action a roller pump uses to pump is similar to trying to roll out dough with a roller. It uses a rolling action to create the pressure. It is also less forgiving of any solids in the material it is spraying.

My top choice would be a centrifugal pump because it has wide open passages and is far more gentile to the material it is pumping. To me a diaphragm pump is in the acceptable range but not as desirable as a centrifugal. Diaphragm pumps can put out 550 psi so you have to be more careful about the pressure, there is a bit more heat and a bit more physical contact. A diaphragm pump will work and used with care won't be harmful to the CT but to me the number one choice would be a centrifugal.

To me you should be running at no higher pressure than you need to get the job done. If you are pumping through 300 feet of hose it will likely take 40-50 psi to do that so if I were doing it I would try to stay in the 40-75 range.

[RLawns]

I have a jet agitated hydro seeder would that work to spray compost tea? perhaps change the nozzle. Also do you need to keep the tank agitated or would the constant moved kill the organisms?

[Turboguy]

It will work fine for spraying compost tea. You might want to go to a different nozzle. I will pm you with some nozzle suggestions. The recirculation won't hurt the tea.

You can also use your unit for hydro feeding if you ever want to and have a high qulaity compost. You might be surprised how much compost you can put in and how fast and easy it is. There are some posts by Barefoot James talking about this a little and if this is of any interest to you you can probably find them pretty easily.

[Tim Wilson]

I was actually going to start a thread on this today. I know very little about spraying rigs but one of my brewer customers brought to my attention two days ago that all sprayers on the market recirculate (agitate) into the tank when the applicator is not engaged. This is simply a means of releasing pressure on the line so it does not blow the lines or pump.

This is NOT good for the microbes in compost tea, especially fungal hyphae. I cannot believe that companies professing to know compost tea and microbial horticulture are selling these for CT application.

We use a homemade rig on the farm and I do have some ideas to create a viable commercial alternative but this will probably take some time during the summer months. It will be electric (operated by 12 volts).

As for the best pumps to use, the fellow who recommended centrifugal (with impellers) under 80 PSI is spot on. You want a high volume low pressure centrifugal pump.

[Turboguy]

RLawns,

Tim brought up a good point that I forgot to mention in my previous post. Using your hydro seeding unit will work great but run it with your agitation valve closed about 3/4 of the way. It will be enough so there is no damage and will minimize the flow going back into the tank. You can also run your engine RPM at about 1/2 throttle or so and minimize the material going back into the tank.

[Tim Wilson]

According to James, these recirculation jets can be shut right off but I don't know if there is any potential damage to the pump, if left running with no flow. The impellers are obviously going to be still turning.

My idea includes a pump which turns off and on as the applicator valve is closed and opened.

[JDUtah]

Tim,

Hey I am ignorant here. I plan to eventually use some hydro-feeding techniques. Question for you. The jet agitation in a hydroseeder SEEMS to be fairly similar to the agitation in your microbulator IF the hydroseeder is adjusted to use the right nozzles and recirculating volume.

The question is, does the agitation in your microbulator effect the fungi?

Then for TurboTurf... do you think one of your units can be modified to perform similar (as far as agitation goes) to a microbulator?

Sorry, one more question Tim. I have heard people argue that the agitation form bubbles alone in a highly aerified CT brewer can harm the fungi.. I have heard others say that this is a none issue. What have you observed?

[dishboy]

I was actually going to start a thread on this today. I know very little about spraying rigs but one of my brewer customers brought to my attention two days ago that all sprayers on the market recirculate (agitate) into the tank when the applicator is not engaged. This is simply a means of releasing pressure on the line so it does not blow the lines or pump.

This is NOT good for the microbes in compost tea, especially fungal hyphae. I cannot believe that companies professing to know compost tea and microbial horticulture are selling these for CT application.

We use a homemade rig on the farm and I do have some ideas to create a viable commercial alternative but this will probably take some time during the summer months. It will be electric (operated by 12 volts).

As for the best pumps to use, the fellow who recommended centrifugal (with impellers) under 80 PSI is spot on. You want a high volume low pressure centrifugal pump.

Will a electric pump like this be OK for not causing damage to CT?
http://www.walkermowers.com/attachments.html

[Turboguy]

According to James, these recirculation jets can be shut right off but I don't know if there is any potential damage to the pump, if left running with no flow. The impellers are obviously going to be still turning.

My idea includes a pump which turns off and on as the applicator valve is closed and opened.

Tim, they can be shut off totally if you are spraying. The need a little movement through the pump. You can shut them off for a few minutes without spraying but an extended period of being shut off totally with the pump still running would start to build up some heat which would likely affect the microbes. Running that way for an extended period will take the seal out of the pump. You can run the agitators so it is just sort of trickling out of the agitation and not have any adverse effects and I am sure it would not affect the tea.

A pump that ran only when you needed it would not be that hard in a unit that was pulled on or mounted on some kind of vehicle such as the Walker that was mentioned but would probably be a bit of a trick in a rig where you were applying the tea with a gun such as a 100 or 200 gallon tank sprayer.

The pump in the photo looks like a surflow which is a decent pump. There are better choices.

I believe I mentioned earlier in this thread that I know more about sprayers than Tea but am doing the best I can to learn more. You brew tea by aerating it but big bubbles are bad and little bubbles are good as I understand it. I almost have a feeling if you took the three best experts in the world and put them together that there would be some areas where their ideas were very different. It is really an interesting subject and there does seem to be a lot of conflicting information. Lawnsite and you guys are really a good resource for learning.

[Tim Wilson]

The question is, does the agitation in your microbulator effect the fungi?

No because I use only air. It is the impellers which cause the damage. Compare it to you with a bunch of spaghetti type appendages going through a water slide over and over. Likely most of your spaghetti will stay attached. Now consider that you need to go through a propeller (or fan blades) each time you enter the slide. Chopped up spaghetti. BTW I happen to know that in paricular flagellates love riding the microbulator:>)

I have heard people argue that the agitation form bubbles alone in a highly aerified CT brewer can harm the fungi.. I have heard others say that this is a none issue. What have you observed?

'from bubbles alone'?

This is bogus, bogus, bogus. I have observed and stated this many times. Of course there are reasonable limits of agitation.

[JDUtah]

No because I use only air. It is the impellers which cause the damage. Compare it to you with a bunch of spaghetti type appendages going through a water slide over and over. Likely most of your spaghetti will stay attached. Now consider that you need to go through a propeller (or fan blades) each time you enter the slide. Chopped up spaghetti. BTW I happen to know that in paricular flagellates love riding the microbulator:>)

'from bubbles alone'?

This is bogus, bogus, bogus. I have observed and stated this many times. Of course there are reasonable limits of agitation.

Makes sense. Thanks for the response! :waving:

[phasthound]

For what it's worth, Elaine Ingham states that recirculation in a spray rig helps keep the ACT oxygenated. James Scotillo uses piston pumps at high pressure when applying ACT to large trees. They get results.

I use a diaphragm pump at about 200psi & am happy with my results. I have not looked under a microscope before & after spraying.

[FOL]

I will post the pics of the my spray rig soon, should have it finished by next week. I will then start some serious testing. I went the low pressure spray rig from Rittenhouse.

My intentions are to head down to TG's "hope you guys are ok" once finished and we are going to do are best to supply some tests results for everyone to see different sprayer setups. Whether it is video like Tim has provided us or at least something. Any suggestions anyone. Give us some time here but I have all the intentions to help everyone with this subject.

One of my biggest concerns getting one of these spray rigs or building my own was the outcome of the herd counts after it has had a chance to go threw these systems. So I will do my best to produce some data, so we can all learn some more about this subject.

[Tim Wilson]

For what it's worth, Elaine Ingham states that recirculation in a spray rig helps keep the ACT oxygenated.

I question the logic of advocating against CT brewers which use water pumps and then advocate the recirculation over and over of finished CT through a water pump.