Ask Andy^®

Yes, Bio-Shield has been used commercially and safely for over 40 years on just about every external building surface, including roofs, skylights, solar panels, walls, painted surfaces, concrete paths and drives, decks, asphalt, and tennis courts.

It contains no bleach (chlorine), salts, phosphates, is non-acidic and fully bio-degradable once diluted and applied to the surface.
Care should be taken when using Bio-Shield around old powder coated aluminum surfaces, where the powder coating is oxidised from UV damage. Most types of outdoor cleaners will leave marks on the darker colours that have oxidised (aged). 


The active ingredients in Bio-Shield are Green Circle approved  in the EPA Safer Chemicals database. 

Follow the simple safety instructions on the bottle for use around pets and plants

Cost per diluted litre is the true cost of any brand of exterior cleaner once it has been diluted to its recommended strength.

For example;

 A 5 litre of Bio-Shield costs NZD$99 and makes 105 litres - $99 divided by 105 litres gives a cost of 94 cents per litre.

 A 5 Litre of Wet and Forget costs NZD$99 and makes 30 litres - $99 divided by 30 litres gives a cost of $3.30 per litre.

 Bio-Shield is only available on-line or by phone order with free delivery by courier. It can be picked up in Auckland by arrangement - add PICKUP to the delivery instructions on your order. 
 Courier delivery is usually on the next working day in Auckland and North Island and in 2 to 3 days in the South Island. Rural delivery can add two days to delivery time.

Some products with the same active ingredient claim to remain on the treated surface and be reactivated by rain for up to 12 months.
The active ingredient in this class of outdoor cleaners is 100% water soluble, and that means several falls of rain will wash it away, usually within 1 to 4 weeks, even on a porous surface. Bio-Shield works to protects a surface from regrowth for up to 4 years by completely and easily killing 99% of all growths and the spores of these growths, before weather removes them from the surface.
 Regrowth will naturally occur over time as new spores are deposited on the surface and begin to regrow when conditions are suitable.

Bio-Shield can be shipped direct to you anywhere in Australia, most cases in 1 to 3 working days. Freight is included in the listed prices. and Bio-Shield is still up to 64% cheaper per diluted litre than buying Wet and Forget in Australia Orders can be placed online here, www.bio-shield.com.au, or by phoning 1800 236 810.

No, Bio-Shield will not kill plants if used carefully by avoiding direct spray onto foliage. In some cases it may cause minor spot damage to the leaves of delicate plants. If in doubt, rinse the leaves off with water.

When used on concrete or similar porous surfaces, the coverage will vary from 3 to 6 m2 per litre.
 A 5L bottle of concentrate will cover 300 to 600 m2
When used on Coloursteel or similar smooth, painted surfaces, the coverage will be 3 to 8 m2 per litre so a 5 L bottle of concentrate will cover 300 to 800 m2

If the moss or lichen growths are thick and heavy, the spread rate will be reduced.
If application is carried out on a hot day, the spread rate will also be reduced due to rapid evaporation.

The Jet-Stream 2.5L  Applicator will cover from 157m2 on concrete, up to 300m2 on Colorsteel with low to moderate growths

Base spread rate for initial clean ups is always 3m2 per diluted litre - this will ensure saturation on most surfaces.
Measure the areas to be treated and match that to a suitable pack size.
 If you intend to maintain any exterior surface with regular treatments of Bio-Shield, we would recommend the 2 x 5L or the 20L to get the best value for money. Bio-Shield has an unlimited shelf life, either diluted or undiluted so can be stored indefinitely.

Bio-Shield is OK to use on house walls and windows. If the surface is not exposed to rain e.g. under the eaves or high on the wall, it will need to be washed down to assist removal of the Bio-Shield and dead growths.  Bio-Shield is ideal for pre-paint preparation of any surface, followed by wash down or water blast clean. Care should be taken when using Bio-Shield around old powder coated aluminium window frames, where the powder coating is oxidised. Most types of outdoor cleaners will leave marks on the darker colours that have oxidised (aged). 

Yes; add the required amount to the sprayer when using Bio-Shield to treat paving with moss, grass, or weed growths in cracks or joins. Ensure the treated surface stays dry for 3 to 4 hours to allow the weed killer time to work.

AVOID ANY OVER-SPRAY ON PLANTS WITH WEED KILLER IN THE BIO-SHIELD SOLUTION - IT WILL KILL THE PLANTS.

Bio-Shield is OK to use around pets providing some basic precautions are taken. Remove feeding / water bowls, bedding and toys from the area to be treated, and keep pets off the treated surface until it dries. Do not feed pets on the treated surface until it has been flushed by rain.

Unlimited when kept in a closed container - whether diluted or undiluted.

Concrete surfaces with light to moderate growth will take 2 to 4 months to clean up. Other surfaces will take from 3 to 12 months to clean up. The amount of growth, the type and condition of the substrate, and the level of rain the surface is exposed to will all affect clean up time.  
When Bio-Shield is used to maintain a previously treated surface that is starting to show the first signs of regrowth, clean-up is rapid, with noticeable improvement in 2 to 3 days in many situations.

Any time of year is suitable provided the ambient temperature is above 10 deg Celsius. Warmer temperatures between 18 to 25 degrees will increase the biocidal activity of Bio-Shield and lead to a faster clean-up.  In summer or hotter weather the best application time is early morning where evaporation is reduced.  The treated surface will stay wet for longer, providing a better clean-up.

Yes, Bio-Shield has been in commercial use for over 38 years, including on roofs that collect drinking water. The collection tank will need to be disconnected before application, and stay off for 2 to 4 weeks (including at least one day of rain) depending on the roof substrate. Porous concrete roofs will take longer to flush clean than Coloursteel You will still be able to draw water from the tank for household use during this disconnection period.
 It is recommended that the tank is full before disconnection and to avoid treating the roof over the summer months in drier areas as there may not be enough rain to flush the roof and refill the tank after it is reconnected Before reconnecting the tank check the water coming off the roof during rain. The water should have no smell or frothing. If smell or frothing is present, refrain from reconnecting the tank until the run-off water is clean.

Yes. Timber decks can take some extra work to cleanup, but if treated regularly every 6 to 12 months they will stay clean. 
Two to three coats are usually required; if the black algae growth is heavy, agitating the wet deck with a yard broom and hose after 2 to 3 months will assist in clean-up. This will return the deck to its natural timber colour. After some weathering a hardwood deck will regain the silver colour. Regular applications of Bio-Shield will keep it free of growth and help retain the silver weathered appearance.

Yes, increase dilution rate to 1:30 = 33ml Bio-Shield to 1000ml water, and apply to the moss patches. The best time for application is in warmer weather so the moss will dry out after Bio-Shield application. After 3 to 4 weeks, rake out the dead moss and resow with grass seed. An application of lime and lawn fertiliser will help to promote healthy grass regrowth that will crowd out any resurgent moss.

Yes we can help with this. There are three options.

• Call us at 0800 800 127 and your order can be manually processed over the phone with your credit card.
• Call us on 0800 800 127 and we can issue an invoice which is payable by deposit at your local bank by telephone or internet banking
• Select Direct Credit as the payment method. When the order is confirmed you will receive an email with our bank account number, simply use you normal method of banking to transfer the payment to this account.