I'm running a 2.5 GPM machine with 3100 psi. I have a little surface cleaner.. SIMPSON Cleaning 80166 Universal 15-Inch Steel Surface Scrubber for Cold Water Pressure Washers, 3600 PSI..
Been down streaming my house wash mix which is 3:2 10% SH to water with a little soap and letting it sit, then using the surface cleaner.
Basically, I'm not doing jack and it's not working. I have to move at a snail's pace and then go back and try to get out the lines and still there are the deep green algae stains left even after the dirt is gone. Some of these driveways are old and the mold and algae is serious around here and I just can't get them clean with what I'm using.
Due to some recent bad breaks I don't have the $ to upgrade equipment just yet. So I was going to try muriatic acid? Is this a good or bad idea? Any other things I can do to get better results?