A drain that drains slowly is not blocked; it is coated. Fat, soap and food solids build a layer on the inside of the pipe until the opening is a fraction of its original size, and that layer decides which of the three methods will actually work.
Match the method to what is in the pipe
Enzyme dosing digests organic fat and keeps a waste line clear, caustic opens a line blocked by grease or hair at a slow pace, and high-pressure jetting cuts through the hard scale and solids that chemistry cannot reach. Use chemistry for maintenance, jetting for restoration.
Prices are Freshway catalogue prices as at 16 September 2026 and are subject to change. Confirm the current price, and whether GST applies, before quoting.
Enzyme dosing: the maintenance answer
Enzyme and bacterial products digest the organic film that soap, fat and food leave behind. They work slowly and continuously, which is exactly what a commercial kitchen, a cafe or a food court needs: the waste line stays clear because the film never gets the chance to build.
Two rules make them work. Dose at night, when the line is not in use, so the product is not flushed away before it acts. And dose continuously rather than in a panic, because an enzyme product applied to a fully blocked drain will sit on top of the blockage doing nothing.
| Product | Use | Price |
|---|---|---|
| Actichem Deozyme | Enzyme digester for organic waste and odour | A$185.00 |
| Enzyme Wizard wheelie bin treatment | Organic digestion and odour, smaller pack size | A$15.60 |
Caustic: effective, with limits
Caustic soda (sodium hydroxide) saponifies fat and dissolves hair. It is genuinely effective in a domestic sink or a urinal waste, and it is the wrong tool in three situations: on a fully blocked line where it sits on top of the blockage; in older or plastic pipework where heat build-up can distort joints; and anywhere the person applying it has not read the label. Caustic is a hazardous chemical requiring gloves, eye protection and ventilation.
Jetting: the restoration method
High-pressure jetting uses a hose with a forward jet to cut through the obstruction and rear jets to flush the debris away. It is the only one of the three that restores a line to its full bore, and it is the standard method for restaurant grease lines, car park drains and any line that has been neglected.
What you need is a pressure washer with enough flow plus a drain hose sized to the pipe. Our Kranzle range covers the three lengths most sites use:
| Item | Reach | Price |
|---|---|---|
| Kranzle drain hose, 10 m | Short runs, sink and floor wastes | A$330.00 |
| Kranzle drain hose, 15 m | Typical restaurant kitchen line | A$330.00 |
| Kranzle drain hose, 30 m with forward jet nozzle | Long runs, car parks and external drains | A$655.00 |
Jetting has one hard rule: it does not go past a broken pipe or an open inspection point without a camera inspection first. Jetting a collapsed line makes the damage worse and the repair larger.
Baking soda and vinegar, and what plumbers actually say
The mixture fizzes because the two ingredients neutralise each other. That reaction produces gas and water, not a solvent, so it does not dissolve fat or hair. What it does do is create a small amount of agitation and a lot of expectation; where it appears to work, the drain was not blocked to begin with.
A drain snake or a plunger handles a soft blockage better than any home remedy, and a slow drain that returns within a week is a sign of coating rather than a blockage — which brings you back to enzyme dosing or jetting.
Odour without a blockage
A drain that smells but drains freely usually has a biofilm problem, and often a missing or dry trap somewhere upstream. Flush the line, dose it with an enzyme digester, and check the floor waste traps before buying anything else. Where the odour is in a bin room or a washroom rather than a drain, the treatment is different again — our air freshening and odour control range covers that side.
Questions we get asked most
- What is the best way to clean your drains?
- Enzyme dosing as routine maintenance, and high-pressure jetting when the line has already built up scale or solids. Chemical-only treatment works for soft blockages but does not restore the full bore of a neglected pipe.
- What do plumbers say about baking soda and vinegar?
- That it is a reaction, not a drain cleaner. The two neutralise each other, so the effect is fizzing water; a plunger or a snake clears a soft blockage more reliably.
- Can you pour vinegar down your drain?
- Yes, and it does no harm in normal amounts. As a drain treatment it is weak, because it is a mild acid and the problem in a slow kitchen drain is fat, which needs alkalinity or mechanical removal.
- What is the best homemade drain cleaner?
- Hot water and a plunger. If you want a home method, a cup of bicarbonate followed by hot water adds mild agitation; neither replaces jetting when a line is genuinely coated.
- When should a professional jet the drain?
- When the drain blocks repeatedly, when the line serves a commercial kitchen, or when the pipe may be damaged. Jetting restores flow, but a camera inspection should come first on any line that has had repeated problems.
References
- NSW Environment Protection Authority — chemicals and trade waste.
- SafeWork NSW — chemicals and other substances.
Repeated blockages on the same line?
Tell us what the drain serves and how often it blocks, and we will tell you whether you need enzyme dosing, a jetting hose or a plumber with a camera. Browse Kranzle jetting equipment or ask our team.