We help Australian homeowners design, price and install beautiful water environments — and connect you with trusted, vetted installers. Education first. Quotes second.
Whether you're dreaming of a koi garden, a statement aquarium, or a backyard water feature — we have a guide for your project and your budget.
Custom backyard ponds, filtration systems, ecosystem ponds, formal concrete builds, and premium Japanese-inspired designs.
Explore koi ponds →Built-in wall aquariums, home installations, office and commercial setups, freshwater and saltwater systems.
Explore aquariums →Pondless waterfalls, rock cascades, modern water walls, garden streams, and decorative fountain installations.
Explore water features →That's usually the wrong order. Koi ponds, aquariums and water features look straightforward online — but the real cost and quality comes from what you can't see in a brochure photo: filtration systems, bottom drains, water chemistry, structural liner choices, pump sizing, and the expertise of the installer.
All prices in AUD, installed. Costs vary significantly with site conditions, filtration specification, and finish level.
| Project type | Typical range (AUD) | Key notes |
|---|---|---|
| Small ecosystem pond (with goldfish or koi) | $5,000–$12,000 | Liner-based, skimmer, basic biofalls. Not suitable for serious koi culture but a beautiful garden feature. |
| Mid-range koi pond (dedicated) | $12,000–$35,000 | Concrete or liner, bottom drain, external pump, biological filtration. Designed properly for koi health. |
| Premium custom koi pond | $35,000–$80,000+ | Full concrete construction, multi-stage filtration, UV steriliser, professional landscaping integration. |
| Luxury Japanese-inspired build | $80,000–$200,000+ | Architectural feature, imported stone, advanced filtration, lighting, bridges, stream systems. |
| Small home aquarium (custom) | $3,000–$12,000 | Custom-sized, built-in cabinetry, proper filtration. Entry point for freshwater setups. |
| Built-in wall aquarium | $15,000–$60,000 | Structural integration, custom glass/acrylic, life support system, lighting design. |
| Commercial aquarium installation | $50,000–$300,000+ | Restaurants, offices, hotels. Includes ongoing maintenance agreements which are significant recurring revenue. |
| Pondless waterfall / water feature | $4,000–$20,000 | Low maintenance, safe for young families, no standing water. Most popular entry-level water feature. |
| Custom rock waterfall feature | $8,000–$40,000 | Natural stone, structural base, recirculating pump. Often combined with gardens or retaining walls. |
A koi pond without proper filtration is not a koi pond — it's a slow-motion fish tragedy. Understanding filtration is what separates buyers who are happy with their pond from those who regret it.
Physically removes solid waste, uneaten food, and debris. The first line of defence. Works like a vacuum — removes visible particles but not dissolved toxins. A pond skimmer is the most common mechanical filter.
Uses beneficial bacteria to convert ammonia (from fish waste) into less harmful compounds. This is the most critical filter type for fish health. Without it, ammonia builds to toxic levels. Clear water does not mean safe water.
Ultraviolet light kills algae and harmful microorganisms as water passes through. Controls green water outbreaks and reduces disease risk. Not a replacement for bio filtration — works in conjunction with it.
These are fundamentally different systems, not just different aesthetics. Many installers will build you what they prefer rather than what suits your goals — unless you know the difference.
Designed to mimic nature. Uses rocks, gravel, aquatic plants, and beneficial bacteria distributed throughout the system to create a self-regulating ecosystem. Filtration is integrated — the biofalls waterfall acts as the biological filter, and the skimmer handles mechanical filtration.
Designed like an outdoor aquarium — optimised for fish health, viewing, and koi growth. Typically concrete construction with external pumps, bottom drains, multi-chamber filtration, and often UV sterilisation. Looks more like a swimming pool integrated into the landscape.
Understand pond types, filtration systems, and what drives cost before you talk to any installer. Knowledge is your negotiating advantage.
Use the quiz to tell us your project type, site conditions, budget, and whether you're building for lifestyle or serious fish culture.
We help you build one consistent brief to send to all installers, so quotes cover the same scope and are genuinely comparable.
We introduce you to vetted installers in your area who specialise in your project type — pond builder, aquarium specialist, or water feature contractor.
Answer 8 quick questions about your project type, site, and budget. We'll build your brief and connect you with specialists who know your category.
Take the 2-minute quiz →Complete cost breakdown — by project type, size, and specification. Plus the hidden costs that blow out budgets.
Why filtration is the most under-specified part of most pond builds, and what a proper system looks like.
The most important design decision buyers make — and why it's often made for the wrong reasons.
From small freshwater setups to large architectural installations — what everything actually costs in 2026.
Why depth matters more than most buyers realise, and the design decisions that affect fish health long-term.
The questions that separate experienced pond specialists from landscapers who build ponds on the side.
For koi, a minimum depth of 1.2 metres (4 feet) is recommended, but 1.5–1.8m is better for most Australian conditions. Deeper ponds maintain more stable water temperatures, which is important in both our hot summers and cooler winters. In areas with predator pressure (herons, cormorants), depth provides refuge. Shallow areas under 60cm should be avoided entirely in a dedicated koi pond as fish cannot escape extreme heat or predators. For high-value koi, some keepers go 2m+ deep.
This is one of the most important distinctions in the industry — and many installers conflate them. A water garden (ecosystem pond) is designed for a balanced natural ecosystem: plants, rocks, gravel, and fish working together. It looks beautiful and is relatively low-maintenance. A koi pond is designed like an outdoor aquarium — optimised for fish health and koi growth. It uses external filtration, bottom drains, concrete walls, and minimal or no planting. You can keep koi in a water garden, but it's not the ideal environment for serious koi keeping. Many buyers who want a "koi pond" are actually better served by a well-designed water garden.
It depends on your state, local council, and the size of the pond. In most Australian states, small garden ponds below a certain volume and depth are exempt development. However, anything over approximately 300mm deep that can hold a child may trigger pool fencing requirements in some councils. Large ponds, any associated structures, and electrical work typically require permits. Our strong recommendation: check with your local council before starting. Most installers operating in your area will also know the local permit requirements.
A well-designed pond with proper filtration typically costs $1,000–$2,500 per year to maintain in Australia. This includes electricity (pumps run 24/7), filter media replacement, water treatments, and a professional annual service or spring clean. Poorly designed ponds or those with inadequate filtration cost significantly more because problems compound. A professional annual service typically runs $300–$600 depending on pond size. Some pond owners do their own maintenance — with the right education and a well-designed system, this is very achievable.
Yes, and this is increasingly popular in Australia. An existing concrete pool structure is actually an excellent foundation for a koi pond — it's already waterproof, structurally sound, and at an appropriate depth. Key modifications needed include: decommissioning pool filtration systems (not suitable for koi), installing pond-appropriate filtration (biological, not just mechanical), removing chlorine residue completely, adding aeration, and usually landscaping around the edges to naturalise the look. Pool-to-pond conversions typically cost $8,000–$25,000 depending on size and the specification of the new filtration system.
Use one written brief and send it to every installer you approach. The brief should specify: pond type (ecosystem vs formal koi pond), approximate dimensions, minimum depth, filtration specification (biological, mechanical, UV), whether you need concrete or liner construction, any waterfall or landscape elements, electrical requirements, and your fish stocking intentions. Without a common brief, quotes are almost impossible to compare — one installer may quote a basic liner setup while another quotes full concrete with professional filtration at three times the price. Our quiz generates this brief for you.
We work with pond builders, aquarium specialists, and water feature contractors in every major Australian city and region.