To use Benz Bio Cleanze or Benz Lightning Cleanze? – that is the question ...

January 05, 2016 2 Comments


We've noticed a lot of confusion on the various forums about which softwash products to use, when to use them, and how power washing fits into the softwashing big picture. So in this post we do our best to clarify the situation.

We've conducted multiple long-term tests in which we observed the effect of various combinations of Benz Bio Cleanze, Benz Lightning Cleanze, and pressure/power/jet washing. What follows in this article is our suggestions for best practices, arrived at through our hands-on observations and experience.

Watch this short video to understand the basics
The video refers to the old names of Benz Lightning Cleanze ("Blackwash") and Benz Bio Cleanze ("Biocidal Wash")

The different characteristics of our softwash biocides

Bio Cleanze is the strongest and most cost-effective quaternary ammonium ("quat") DDAC biocide in the UK and Ireland. It has a residual biocidal effect because it requires contact with organic matter to break down. Therefore some of the active ingredient is able to remain and kill spores that land on the surface in the months following treatment.

The combination of warm weather and high rainfall facillitates the rapid spread of algae. This is true especially of horizontal surfaces such as paths and drives. But on surfaces treated with Bio Cleanze we have noticed no sign of algae growth returning even after 12-24 months, which shows how powerful the residual biocidal effect is.

This affect can be seen most noticeably on surfaces that have been pre-cleaned using either Lightning Cleanze or a power washer as there is less organic matter to break down the active ingredient (DDAC). 

Lightning Cleanze is a powerful formula combining a sophisticated surfactant, a pleasant scent, and high quality sodium hypochlorite. It does not have a residual biocidal effect (neither does any sodium hypochlorite based product) because the sodium hypochlorite breaks down within 30-60 minutes of application. It does not require contact with organic matter to break down, although contact speeds up that process.

Lightning Cleanze is the treatment of choice for all soft surfaces that should not be power-washed – such as sandstone, limestone, and render – which have been contaminated with heavy organic growth.

Treating surfaces with a softwash biocide

On vertical surfaces, which do not accumulate damp, treatment with Lightning Cleanze may be sufficient. A treatment with Bio Cleanze 12 months later, followed by a bi-annual treatment with Bio Cleanze will keep most walls perpetually clean. For walls in damp, shaded areas, an annual treatment with Bio Cleanze may be necessary.

Horizontal surfaces suffer from damp much more than walls, and so the potential for re-contamination is much greater. Concrete paths, patios, and drives come up well with Lightning Cleanze and benefit from a post-treatment of Bio Cleanze to offer residual biocidal protection.

Quick tip: We recommend Bio Cleanze for tarmac as our experience is that this leaves the tarmac looking good and deals with most biological growths within 24-48 hours.

Some infestations are harder to shift than others. For example, the black lichen that can grow on concrete paths and patios can be a really tough proposition to remove. The choice of which method to use depends upon the severity of the contamination, the likelihood of re-contamination, and on whether or not you have access to a power washer. We've used this example of black lichen on concrete paths and patios to illustrate the possible combinations that softwashing offers:

1) Light power wash followed by Bio Cleanze (works well and provides residual biocidal effect)

2) Lightning Cleanze > Light power wash & rinse > Lightning Cleanze > Rinse (works well on severe contamination and although it has no residual biocidal effect this method reduces the materials cost)

3) Lightning Cleanze (1-2 applications) > Light power wash & rinse > Bio Cleanze (loosens up and removes severe growths prior to power washing, then offers residual biocidal protection)

4) Lightning Cleanze (1-3 applications) > Bio Cleanze (when a power washer is not available)

Dilution rates: If the contamination is not too severe, and on most non-porous surfaces, Lightning Cleanze @ 10:1 may be sufficient but for severe contamination use 5:1.

Bio Cleanze can be used to great effect at 50:1 and also as strong as 20:1. Do not apply to surfaces that will be walked on by young children or animals at a strength greater than 40:1 and allow the surface to dry completely before they are allowed access.

Quick tip: Two successive treatments at 50:1 can be more effective than a single treatment at 25:1 because this allows for the active ingredient to have a longer contact time with, and a deeper penetration into, the biological growth.

You'll find from experience what combination and which dilution rates work best for specific situations and surfaces. We cannot give absolute figures and recommendations because the climatic variables of temperature, wind, sunlight, rainfall, shading, and the nature of the surface being treated, all vary from region to region and from job to job.

The experience needed to calculate these variables makes softwashing a skilled profession, which makes it both interesting and justifies your fees.

Quick tip: Whenever you apply Bio Cleanze following Lightning Cleanze always thoroughly rinse the surface to ensure as much of the Lightning Cleanze surfactant as possible is removed. And we suggest allowing a full 60 minutes for the sodium hypochlorite in Lightning Cleanze to completely break down before treating the surface with Bio Cleanze.


Important information about softwash surfactants

There are thousands of amine surfactants and not all are biodegradable. And some will break down sodium hypochlorite even before it reaches the surface to be cleaned.

The surfactant we use in Lightning Cleanze is highly specialised, biodegradable, and was developed by our industrial chemists specifically for use in Lightning Cleanze. The use of this high quality surfactant ensures Lightning Cleanze remains stable and does not break down the sodium hypochlorite before it reaches the surface to cleaned.

Combined with the highest quality sodium hypochlorite in Lightning Cleanze (beware cheap hypo products as all hypo is not created equal – they vary in strength, purity, and conformity with REACH regulations) means this is a very high quality product. Comparing Lightning Cleanze with cheap hypo, cheap surfactant, and cheap scent is like comparing a new BMW with an old banger.


Rinsing technique following Lightning Cleanze treatment: It's important to rinse Lightning Cleanze from the surface 30-60 minutes following application. Also to rinse between treatments if the surface requires more than one application. The fastest and most effective rinsing method is to use a power washer at low pressure, using a rinsing nozzle (a hosepipe will do but is less effective). If you don't have a machine with adjustable pressure, use a fan jet held well away from the surface so as reduce the pressure on the surface and not to cause damage.


When to use Bio Cleanze:

  • Softwashing roofs.
  • Following power washing.
  • Following a treatment with Lightning Cleanze.
  • Softwashing tarmac.
  • Rendered walls that are stained red or green.
  • Historic buildings where care of the structure is important.

Examples of when to use Lightning Cleanze:

  • Vertical surfaces such as rendered walls, if stained black.
  • Surfaces contaminated by black stains and lichen, including concrete patios, paths, and drives.
  • Soft surfaces that would be damaged by power washing, such as sandstone, limestone, and render.
  • Historic buildings where care of the structure is important.
  • When your customer demands the fastest possible results.


 Examples of when to use a power washer:

  • Cobblelock paths and drives to clear out the weeds, followed by Bio Cleanze.
  • Heavy lichen infestation in concrete paths and patios, in conjunction with Lightning Cleanze and Bio Cleanze.
  • Rinsing both horizontal and vertical surfaces, using a rinse nozzle or fan jet (keep pressure on the surface low by turning pressure down or keeping a fan jet well away from the surface)

We hope this helps clear away the confusion as to what works best when it comes to  softwashing best practices.


Ben, Leo & Fiona


Click here to explore the full range of Benz softwash cleaning products

Benz Softwash Bio Cleanze DDAC biocide & Benz Softwash Lightning Cleanze SH sodium hypochlorite biocide

2 Responses


March 17, 2016

Hi Tim

1) If you have pressure washed a drive and it is clean, then we recommed post-treating with Biocidal Wash at 40:1 (winter) and 50:1 (summer) to provide residual biocide protection. There is nothing to be gained by treating an already clean surface with Blackwash or any other SH product.

2) Hosing down paths and patios is a good idea if there is a lot of mud and organic growth. It’s a simple form of pre-cleaning that will allow the chemical to work more effectively. Brush away all puddles and ideally allow the surface to dry as much as possible before treating with Blackwash so the surface water does not further dilute the chemical.

But if the paths are clean then you can apply Blackwash to a dry surface, usually at 5:1.

I hope this helps.

Wishing you soft washing success!


Tim Ogburn
Tim Ogburn

March 08, 2016

i have two questions please….1) When pressure washed a block drive i used to use 5 to 1 SH is blackwash ok to use at same dilution or should i be opting for 10.1

2) when using black wash on concerete paths is it ideal to hose area then apply blackwash or is it ok as the above question
Many thanks

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