Downstream Injector for Driveway Concrete

Hey there, I am new to the pressure washing community.
I am wanting to know how well does Pre and Post-treatment with 12.5% SH running through a Downstream Injector actually work. Since I am just starting out I am building up to a softwash system. Until then my options for spraying chem is hand pumping or Downstreaming.

Lots of guys pre/post treat with just house wash mix, so DS’ing straight 12.5% would work. But it all depends on how much organic build-up you’ve got to remove.

1 Like

This is a must watch if you want to learn some good tips on flatwork.


Also, aren’t we pretty much having the same discussion in this thread currently?

1 Like

Yeah I posted a picture in the above thread of downstreaming 10.5% bleach on concrete pre post. Might be the greatest but I believe it’s plenty sufficient to do most flat work. Obviously there will be exceptions to this where you will need a pump spray possibly or a degreaser to help with certain oils or bad spots.

Truth be told, downstreaming 12% with my 8gpm doesn’t put much out, barely useful for housewashes and just kinda lightens stripes after marginally dirty driveways. I’m constantly using my 12v to hit tougher spots like gutters and black concrete.

Using a 4 or 5.5gpm unit puts out a lot more SH when downstreaming.

1 Like

That’s a bit of an exaggeration.

I have an 8 and a 5 on my trailer. I’ll take the 8 everyday for a house wash hands down.

For gutters it’s easier just to have a pump up with 3-4% mix to use as needed than pulling out the 12v with 100+ ft of hose.

Pump up, are your gutters 5’ off the ground?

1 Like

Try the Super Suds Sucker. I use it with 8 GPM. It’s spendy but a big difference when compared to the GP high draw. I don’t know how much it pulls. Just know it cleans better. Bought it mid summer and just had to replace it a week ago. Bought the rebuild kit to fix the old one.

1 Like

I bought a Super Suds Sucker as well. I haven’t washed with it, but its installed and ready to go. I’m running a 8gpm and was getting .7 on my mix with a 2.3 injector. I’m now running a 2.1 with the Super Suds Sucker.


lol. I can get a good 15’ with my pump up. I don’t have to use it that often though. Maybe your gutters are dirtier down there.


It’ll draw better simply because you went to a 2.1.

Trying using the 2.1 GP first and you’ll get similar results to the SSS. Most of us using an 8 are running a 2.1.

I did run a 2.3 for about 6 months and didn’t have any issues.

I had about a 10ft run to my mix tank with the 2.3 for the .7 mix, and it would clean with multiple passes. I did try the 2.1 alone with a 2ft run I relocated my mix tank and got great results. I just added the SSS and haven’t tried it. The longer the hose from the mix tank to my schertz box, the weaker the mix seems.

SSS draws no more than a GP. You really want to believe it does because you got conned into paying so much for it. I bought dozens of them before I realized John had pulled a fast one on everyone. Ds’ing straight 12.5 is way too strong of a mix for houses. Cut it 50/50 with water or use the gp injector with orifices. If you’re 8 isn’t cleaning with 12.5, you have the wrong injector or other issues.


You dilute your 12.5 on the 8 or run it straight?

I diluted It for about 20 years. Last couple of years I run it straight but cut it 50/50 with the injector orifice


@Thewashingguy a pump sprayer is fine until you get a 12v and some hose. Its actually faster on small jobs. 3-4% works.

1 Like

@Innocentbystander when you swap out the injector orifice, are you talking about this injector?

Yes indeed

1 Like

Yeah, it’s called really nasty houses.:laughing: