# Downstream ratio



## CustomDesignCoatings

We have a cedar siding stain job coming up and I want to bounce my math off of someone. 

I will be running two machines a 4000psi/4gpm and a 3200psi/5pgm both with 100ft of pressure hose attached. The injectors are the HD injectors from Pressure Tek. 

I will be using a mix of 12.5%SH and Elemonator. If the downstream in 10:1. Would straight 12.5% give me 1.25%sh hitting the surface? If I did a mix of 3:1 SH to water would it look like this

12.5x.75=9.56%
9.56%/10=.956% hitting the surface 

There is a lot of surface mold and some algae is areas and I have researched and spoken with other who advise me 1-2% hitting the surface will do what I need but straight SH seams hot even down streaming. 

After wash we will be applying a solid latex stain. 

Thoughts?

Respectfully,
Brian


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## Ultimate

Most guys running 4gpm machines run a mix of 3 sodium hypo/2 water or 2 sodium hypo/3 water. Depending on temps outside. 

If you want to test how much soap you are truly getting on your specific setup, get a 15 gallon drum and 1 gallon bucket. Stick the injector tube into the gallon jug then spray water into the 15 gallon drum. When the injector has drawn the full gallon, see how much is in the 15 gallon drum then you know what your ratio is. 

If the mildew is above average, nothing wrong with being a little hot. Just plenty of rinsing of the surface and surrounding plants.


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## PressurePros

You won't get a hot enough solution to kill heavy mold. One way to make the strongest possible solution is to use an undersized injector but you will be better off with an X-jet and playing with your mix ratio.


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## CustomDesignCoatings

PressurePros said:


> You won't get a hot enough solution to kill heavy mold. One way to make the strongest possible solution is to use an undersized injector but you will be better off with an X-jet and playing with your mix ratio.


Ken,

What's the purpose of the x-jet....less dilution?


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## CustomDesignCoatings

Rained hard here yesterday but thought I would play with some mixes today. 

This is straight 12.5% downstreamed. Wood was already damp but not soaked. Started melting mold in about a minute. I'm going to try 4:1 in a 5er and see what it does


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## PressurePros

CustomDesignCoatings said:


> Ken,
> 
> What's the purpose of the x-jet....less dilution?


Yes you get more like 3:1.

I didn't realize you had a finish on the wood. That makes a huge difference in removing mold with lower sodium hypochlorite % solutions. That looks great!


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## jeffnc

CustomDesignCoatings said:


> What's the purpose of the x-jet....less dilution?


I ended up going with X-Jet instead of downstreaming, and my understanding is what PP originally referred to - "playing" with the dilution. The point is, you can just pop different proportioners in there and change the percentage to whatever you want. To me, that's easier than always trying to get the chemical percentages right in your supply tank/bucket. It makes it easier to change brands or versions and still keep the concentration you want.


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## tigerwashnola

jeffnc said:


> I ended up going with X-Jet instead of downstreaming, and my understanding is what PP originally referred to - "playing" with the dilution. The point is, you can just pop different proportioners in there and change the percentage to whatever you want. To me, that's easier than always trying to get the chemical percentages right in your supply tank/bucket. It makes it easier to change brands or versions and still keep the concentration you want.


This is exactly why I like the x-jet. so much more flexibility and control with your mix and the strength/dilution ratio. X-jet FTW!


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