FREE SHIPPING* on 90% of Products
Next Business Day Dispatch
60 Day Returns

FREE SHIPPING* on 90% of Products

LAST ORDERS Mon, June 26. Closed for stocktake until Mon, July 3.

We’re experiencing some payment issues. Call 1300 283 387 if you can’t purchase online.

FREE SHIPPING* on 90% of Products

Next Business Day Dispatch

Next Business Day Dispatch

, , , ,

Biostim Liquid (5L)

$249.99 INC GST


Biostim—Liquid (5L)

Biostim Liquid is the fastest acting probiotic in the Biostim range. The solution spreads quickly through your entire water column and wakes the microbes up. These “good” microbes actively produce enzymes, speeding up the breakdown of organic waste, which clears the water of cloudy organic debris. The “good” bacteria also consume nutrients (e.g. nitrogen, phosphorus) in the water because they need to for their own survival. Fewer nutrients means less food available for pests like algae and aquatic weeds. 

A 100% natural biological stimulant 

Biostim is a 100% natural biological stimulant made of bacterial cultures, enzymes and nutrients. You can think of it as a probiotic that feeds the “good” microbes (aerobic bacteria) in your dam, much the same way you might eat Greek yoghurt or drink Kombucha to feed the “good” microbes in your gut. These “good” (aerobic/oxygen-loving) bacteria actively produce enzymes, speeding up the breakdown of organic waste and degrading sludge. This reduces the amount of food available for the things you don’t want to grow.  

Less nutrient rich sludge = less compost fertiliser 

These “good” microbes, provided by Biostim, feed on organic material (aka the food source of algae and weeds) and draw nutrients directly from your water. Reducing the overall nutrient levels in your dam, the bacteria eventually starve out pests like algae and weeds (because, if the good guys are growing strong, there’s not much food left for anything else).     

Biostim can also clear water of organic material, i.e. the cloudiness in water from microorganisms and decaying organic material. This is not to be confused with muddiness from inorganic material; Biostim does not clear muddy water.  

Watch the video below to see the impact of Biostim on algae and blue-green algae in 11 weeks.

Other benefits 

Target specific areas: You can use Biostim to control sludge in the entire water body, or in specific area, such as around irrigation suction pipes, under aquaculture cages, or in swimming areas. 

Reduce odour: Biostim also helps reduce odour because the “good” bacteria outcompete “bad” (anaerobic/oxygen-hating) bacteria that produce nasty, smelly chemicals like methane and hydrogen sulphide. 

Non-toxic, chemical-free: Biostim is a 100% natural product that contains no harsh chemicals. This means it will not harm fish, birds, pets, or people. 


Biostim Liquid should be diluted at the rate of one part Biostim Liquid to nine parts pond/dam water and then be sprayed or poured over as much of the water’s surface area as possible. Benefits are usually seen after just a couple of weeks with sludge/organic matter being the most significantly reduced over the course of summer when bacteria are most active. Problem areas can be treated heavily without having to treat the entire water body. Biostim is safe to use at higher doses. 

Dose Rates  

The following dose rates are guidelines that may need to be increased or decreased according to your individual conditions. Results will depend on factors such as sludge composition, water temperature, and water movement (circulated, aerated water provides best results).  

It’s recommended you treat your water, monitor the results, and adjust your dose rate based on these results.  

Monthly Dose Rate—Large Water Bodies

1L Biostim Liquid per megalitre (million litres).

Monthly Dose Rate—Small Water Bodies

20ml Biostim Liquid per 1,000 litres.

This can be adjusted based on individual results. Note: Biostim Liquid can be dosed at higher rates when required but care should be taken to ensure adequate aeration in fish ponds.


What customers say  

“In our ponds that are too small for aerators, we used Biostim pellets on their own and have noticed a huge reduction in algae.”  

Andy Hart, Horticultural Curator, Department of Environment, Water and Natural Resources, SA  

“We had an old irrigation system blocked by weeds. Our dam was also riddled with black sludge. Scott recommended both aeration and Biostim and within six weeks the dam became so clear I could see to the bottom of it! I was chuffed we could fix the issue without the use of chemicals.”  

Michael Grant, Owner Grant’s Citrus Farm, VIC  

“Visiting ducks and our pet geese were continuously fouling the dam. Scott recommended a number of systems to improve the water quality. We’re very happy with our final choice, the windmill aeration system combined with the Biostim pellets and liquid. They’ve completely cleared up my dirty dam!”  

Greg Lewis, Canterbury, Victoria 

Other sizes

Biostim Liquid (1L)

Biostim Liquid (20L)

Weight 6 kg
Dimensions 30 × 14 × 30 cm

You may also like…