Short answer: Yes, a house with a koi pond can be safely soft washed, but only if the crew treats the pond as a no spray zone from the start. On this Frankfort job we covered the pond, shut down the waterfall pump, pre soaked the plants and ground around it, worked the wall closest to the water by hand at low volume, and rinsed away from the pond every single time. Zero solution reached the water and every fish was fine when we packed up.
We washed a home in Frankfort, Illinois this morning. Two things made it different from a normal house wash. The gutters had algae growth so thick you could see the texture of it from the driveway, and the backyard held a koi pond the homeowner had been building out for years.
Either one of those on its own is a normal day. Together they force you to slow down and plan the job before a drop of anything comes out of the hose. Here is exactly how we handled it.
Before and after of the gutter face on this Frankfort, IL home. The dark band across the top is live algae, not dirt.
What was actually growing on the gutters
The homeowner called it dirt. It was not dirt. It was a living algae colony, most likely gloeocapsa magma along with common green algae, and it had been feeding on the moisture that sits on a north facing gutter face all summer. Northern Illinois humidity in July and August is close to perfect for it. Shade from mature trees over the back half of the roof kept that side of the house damp all day, and the growth had gotten thick enough to hold water on its own, which only speeds the whole thing up.
You can tell live algae from other gutter staining by how it comes off. Algae is organic. It releases when you kill it, which means the right chemistry does the work and the pressure washer barely has to show up. That is what you are watching in the video below. The gutter face changes color the moment the solution touches it.
Algae is not the same thing as tiger stripes
This trips up a lot of homeowners, so it is worth separating the two. Those vertical black streaks people call tiger stripes are not organic at all. They are oxidation and roof runoff residue that has bonded electrostatically to the aluminum. No amount of pressure and no amount of algaecide will lift them. That takes a dedicated gutter brightener applied by hand, panel by panel, and it is priced as its own service for a reason.
What this Frankfort house had was true organic growth, which responds to a proper soft wash. We told the homeowner that up front so they knew what they were paying for and what the finished gutter would realistically look like. If your gutters have both, you need both services, and any company that tells you one wash handles everything is guessing.
Then we walked around back and found the koi pond
The pond sat maybe twelve feet off the back wall of the house, with a small waterfall feature, planted edges, and a group of koi the homeowner clearly cared a great deal about. He asked the question every pond owner asks. Is the soap going to hurt my fish?
Honest answer: yes, it absolutely can. A standard house wash mix is sodium hypochlorite plus a surfactant. The surfactant is the bigger problem for fish. It strips the protective slime coat off them and interferes with oxygen exchange across the gills, and it does not take much of it. Contractors have killed koi with a small amount of overspray drifting into the water. This is not a maybe.
That is why we plan around a pond instead of hoping for the best.
How we protected the pond, step by step
- Shut down the pump and waterfall first. Moving water pulls air and anything floating on the surface into circulation. A still pond with a covered surface is far easier to protect.
- Covered the entire surface. We laid tarps across the pond and weighted the edges so nothing could drift in, and so nothing that landed on the tarp could roll off into the water.
- Pre soaked everything around it with clean water. Saturated ground and saturated plants absorb far less of anything that reaches them. Wet plants also dilute on contact instead of holding concentrate.
- Dropped the strength on the back wall. The wall closest to the pond got a weaker mix worked in by hand with a brush rather than sprayed, which gave us complete control over where every ounce of it went.
- Rinsed away from the water, never toward it. Every rinse pass on that side of the house moved water out toward the side yard and away from the pond basin.
- Kept a fresh water hose running the whole time. If something had gone wrong, dilution needed to be instant, not something we went looking for.
- Uncovered and restarted the pump only after the final rinse. Not while we were still packing hose, and not while anything on the house was still wet with solution.
None of that is complicated. It is just time, and it is the part a company cutting corners on price skips. We would rather add forty five minutes to a job than explain to a homeowner why his koi are floating.
Watch the gutter come clean
Filmed this morning in Frankfort, IL. The algae releases on contact with no pressure on the gutter face.
What the finished job looked like
The gutter faces came back to their original white. The siding lost the light green film it had picked up on the shaded side. Window frames, soffit, and fascia were cleaned in the same pass, which is standard on every house wash we do rather than an add on. The pond was uncovered, the waterfall was running again, and the fish never stopped acting like fish.
The homeowner is now looking at putting the house on an annual schedule so the algae never gets a foothold like that again. That is the smart move in Frankfort. Once growth is established it comes back faster every year, and a maintenance wash costs less than a restoration wash.
Green Pro Services holds a 5.0 star rating across 99 Google reviews. We are licensed, insured, and OSHA 1910 trained, and we treat delicate landscaping, water features, and pets as part of the job scope rather than someone else's problem.
Do you have a pond, a pool, or koi?
Tell us when you book. It changes nothing about the price and everything about how we set up. The homeowners who lose fish are almost always the ones whose contractor found out about the pond after the truck was already unloaded. Five seconds on the phone prevents all of it. You can reach us at (815) 650-0397 or request a free estimate online.
More on the services in this post: house washing, gutter cleaning, and our service page for Frankfort, IL.
Frequently Asked Questions
Pressure Washing in Frankfort, IL
It is safe when the crew plans for it. The cleaning solution used on siding contains surfactants that are toxic to koi even in small amounts, so the pond has to be covered, the pump shut off, the surrounding ground pre soaked, and all rinse water directed away from the basin. Tell your contractor about the pond when you book, not when they arrive.
Most single family homes in Frankfort fall between roughly $300 and $700 depending on square footage, number of stories, how much organic growth is present, and whether gutter faces and windows are included. We quote from measurements rather than over the phone guesses, and the estimate is free.
Pressure washing uses high pressure water and belongs on concrete. Soft washing uses low pressure and a cleaning solution that kills algae, mold, and mildew at the root. Siding, roofs, and gutters get soft washed. Running high pressure on vinyl siding forces water behind the panels and can void the manufacturer warranty.
Not when the beds are pre soaked with clean water before the wash and rinsed again afterward. Saturated soil and wet foliage dilute anything that reaches them. Damage happens when a crew sprays over dry plants and leaves them sitting.
Those streaks are oxidation and roof runoff bonded to the aluminum, not organic growth. A house wash removes the algae around them, which can make the streaks look more obvious than before. Removing them requires a dedicated gutter brightener applied by hand, which we offer as a separate service.
Once a year for most homes. Houses with heavy tree cover, north facing walls, or nearby standing water often need it annually without exception, because shade and moisture let algae reestablish quickly through an Illinois summer.
Yes. Green Pro Services covers Frankfort, Mokena, New Lenox, Monee, Manteno, and the surrounding Will County and Kankakee County communities, plus the south suburbs of Cook County.
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