Frequently Asked Questions

Wai Gardens designs, installs, and maintains hydroponic and aquaponic food systems for homes, schools, and businesses across Oʻahu. We handle everything: site assessment, custom system design, installation, ongoing maintenance, and plant supply. So you can grow fresh, pesticide-free food at home with minimal effort. We are based in Mililani and serve all of Oʻahu.

We are based in Mililani, Hawaiʻi (Central Oʻahu) and serve the entire island of Oʻahu, including Mililani, Mililani Mauka, Wahiawā, Waipiʻo, Pearl City, ʻAiea, Kapolei, ʻEwa Beach, Honolulu, Kailua, Kāneʻohe, the North Shore, and the Leeward Coast. Travel fees may apply for locations more than 20 miles from Mililani.

The easiest first step is our free site evaluation. Fill out the form on our Evaluate Your Space page and we will reach out within one business day to schedule a visit. During the visit we look at your available space, sun exposure, water access, and what you want to grow. From there we put together a written proposal: system type, size, pricing, and maintenance options at no charge and with no obligation.

Residential hydroponic systems start at $899 for our 42-plant NFT tower system. Custom designs for larger spaces or specialty crops are quoted after a free site evaluation. Aquaponic systems typically start higher due to the fish tank, biofilter, and plumbing involved. Contact us for a quote based on your specific goals and space. Ongoing maintenance plans start at $149 for a one-time service visit.

No experience is required. We design and install the system, handle the initial cycling and plant setup, and train you on daily care — which typically takes five minutes or less. Our maintenance plans mean you can have professional oversight as often as weekly if you want. Many of our clients had never grown anything before their first system.

Hydroponics grows plants in a nutrient solution you mix and add. It is precise, fast, and relatively straightforward to manage. Aquaponics replaces that nutrient solution with fish waste — fish live in a tank, their waste feeds bacteria, bacteria produce the nitrates that feed the plants, and the plants clean the water for the fish. Aquaponics is more complex to set up and cycle, but once running it is largely self-sustaining, uses 90% less water than in-ground gardening, and grows protein alongside vegetables. Many of our clients run both.

We install NFT (Nutrient Film Technique) rail systems, DWC (Deep Water Culture), vertical tower systems, and ebb-and-flow systems. The right choice depends on your space, what you want to grow, and how much you want to manage. NFT towers are our most popular residential option — compact footprint, high plant count, excellent for leafy greens and herbs. We recommend the best fit during the free site evaluation.

Almost everything thrives hydroponically in Oʻahu's climate. Leafy greens (lettuce, kale, chard, bok choy, chijimisai, arugula), all culinary herbs (basil, cilantro, mint, parsley, lemongrass, Thai basil), and fruiting plants (tomatoes, peppers, cucumbers, eggplant, strawberries) all do very well. Root vegetables are harder in NFT systems but possible in media-bed setups. We help you choose the plant mix that matches your kitchen and your system's capacity.

A well-designed hydroponic system uses 70–90% less water than traditional in-ground gardening. The nutrient solution recirculates through the system rather than draining into the soil. In Oʻahu's climate, a mature 42-plant tower system uses roughly 4–8 gallons of water per day at full plant load during a hot week — most of that is evapotranspiration from the plants, not waste.

For leafy greens and herbs, you can expect your first harvest 4–6 weeks after transplanting seedlings into a new system. We transplant seedlings at the 2–3 true-leaf stage, and lettuce and most herbs reach harvest size in 5–7 weeks total from seed. Fruiting plants like tomatoes, peppers, and cucumbers take longer — typically 10–16 weeks from transplant to first harvest.

A healthy system needs a 5-minute daily check (pump running, water level, plant visual), a 20–30 minute weekly check (pH and EC test, top-off nutrient solution, harvest and trim), and a full reservoir change every 2–3 weeks for greens. We offer maintenance plans from weekly visits to quarterly, so you can choose how much you do yourself and how much you leave to us.

For leafy greens and herbs, keep your reservoir pH between 5.8 and 6.2 and EC (electrical conductivity) between 1.0 and 1.6 mS/cm. For fruiting plants, ramp EC up to 2.0–3.0 mS/cm. We provide a cheat sheet with every installation and walk you through testing during the handover. Our maintenance clients never have to track this themselves — we check and adjust at every visit.

A small backyard media-bed aquaponic system for a residential home on Oʻahu typically starts in the $2,000–$4,000 range installed, depending on size, fish species, and grow-bed configuration. Larger IBC tote systems and school installs are quoted individually after a free site assessment. Monthly maintenance plans are available separately. Contact us for a free estimate.

For residential systems we primarily use Mozambique tilapia — hardy, fast-growing, edible, and well-suited to Oʻahu temperatures. For clients who want an ornamental water feature alongside their food garden, we also work with koi and goldfish. Channel catfish are a good option for larger or shadier systems. We navigate the DLNR aquaculture permit requirements as part of every build — some species and commercial operations require permits.

For most private residential aquaponic systems using tilapia, no permit is required. However, certain tilapia species, commercial operations, and systems connected to natural waterways do require DLNR aquaculture permits. We handle the permit research and paperwork as part of every aquaponics build so you are fully compliant from day one.

A new aquaponic system takes 4–8 weeks to cycle fully. During cycling, beneficial bacteria colonize the biofilter and establish the ammonia → nitrite → nitrate conversion pathway that makes the system safe for fish and productive for plants. We manage the cycling process as part of every build and only add fish once water chemistry confirms the system is stable.

Most home aquaponic systems need a 30-minute check every 2–4 weeks (pH, ammonia, nitrite, nitrate, dissolved oxygen, biofilter inspection) and a deeper clean every 3–6 months depending on stocking density. We offer monthly and quarterly maintenance plans so you never have to track it yourself. Daily care is typically 5 minutes — feeding the fish and a quick visual check.

Yes — for tilapia and catfish, that is part of the point. Tilapia raised on commercial aquaponic feed in a clean, well-maintained system are safe to eat and quite good. For koi and ornamental goldfish, the answer is no — we use those for clients who want a water feature. We discuss your goals during the site assessment and recommend the right fish species accordingly.

Fish need aerated water — without the pump running, dissolved oxygen drops fast and fish can die within hours. For all aquaponic builds we discuss backup options: battery-powered air pumps, UPS units, or manual aeration plans. For school and koi systems where loss would be especially costly, we strongly recommend a battery backup. We factor this into the system design from the start.

We offer four tiers. Instant Aloha is a one-time service or repair visit starting at $149 — no commitment, covers everything from reservoir cleaning to pest management. No Worries Quarterly ($100–$300/visit) is for confident gardeners who want professional deep-cleaning four times a year. No Worries Monthly ($100–$300/visit) adds free plant delivery and monthly oversight. No Worries Weekly (starting at $249/month) is full-service — we handle everything weekly and replace plants as you use them at no extra charge.

Every maintenance visit includes: reservoir inspection and cleaning, water level check and top-off, algae control, pH and nutrient testing and balancing, filter and pump inspection, all-natural pest management, and a detailed service report emailed after the visit noting what we found, what we fixed, upcoming harvests, and anything to watch for. Weekly plans also include plant pruning and free plant delivery.

Yes. We do rescue maintenance for backyard systems built by other installers or built DIY. We come out, audit the system, repair what needs fixing, and put you on a regular maintenance plan. Contact us with photos of your setup and a description of the issue and we will give you an honest assessment.

We aim to respond to all inquiries within one business day. For urgent issues like a system malfunction, pump failure, or fish health emergency, reach out by phone at (808) 726-9493 and we will prioritize your visit. Maintenance plan clients receive priority scheduling.

Yes. All system components we supply come with manufacturer warranties, and we warrant our installation workmanship for 90 days. For aquaponic systems, fish lost during the cycling and establishment period due to design-related issues are replaced at no charge. We stand behind what we build.

Yes — school systems are one of our specialties. We design, install, and maintain hydroponic and aquaponic systems for Pre-K through 12th-grade classrooms across Oʻahu. We build systems sized and configured for the classroom, supply NGSS-aligned curriculum your teachers can pick up and run, train your staff, and offer ongoing maintenance so the system keeps working year after year.

We provide lesson plan outlines aligned to Hawaiʻi DOE standards and NGSS for Pre-K, Kindergarten, 1st, and 2nd grade, with frameworks for higher grades. Topics covered include the nitrogen cycle, water chemistry, biology, ecology, food sovereignty, and ʻāina-based learning. Teacher training is included with every school install. We also offer optional in-classroom workshop sessions led by our team.

Yes — several funding sources apply. The USDA Patrick Leahy Farm to School Grant Program, the Ulupono Initiative / Hawaiʻi Community Foundation, the Public Schools of Hawaiʻi Foundation Good Idea Grants, and the State of Hawaiʻi Farm to School Action Plan Resilience Office have all funded similar projects. We help schools identify applicable grants and can assist with the application narrative. Contact us to start that conversation.

School system pricing depends on classroom size, grade level, whether you want a mobile cart system or a permanent installation, and the scope of curriculum support. Contact us for a free assessment — we will propose options at different price points and can work within grant budget constraints. We have designed systems for under $3,000 and full classroom installations in the $8,000–$15,000 range.

Yes. Our online shop sells pesticide-free hydroponic keiki plants, herbs, leafy greens, fruiting plants, and specialty varieties grown right here in Mililani. Plants can be ordered online for pickup or local Oʻahu delivery. We also offer curated bundles — our Salsa Kit (Roma tomato, jalapeño, cilantro, green onion) and Hot Pot Kit (bok choy, chijimisai, lombok, mizuna) are popular gifts and a great way to start a small garden.

Yes. All plants we sell and supply to maintenance clients are grown without chemical pesticides. We use all-natural pest management in our growing operation and for all on-site pest control during maintenance visits — safe for children, pets, and the environment. Our plants are sprouted and grown on Oʻahu, minimizing travel time and emissions.

Most of the plants we sell will do well in either soil or a soilless hydroponic medium. They are started in rockwool or coco coir plugs and transplant easily into either a hydroponic net cup or a standard soil pot. If you are buying plants for a soil garden, just let us know and we can advise on transplanting.

Wai Gardens was founded in Mililani by Tyler Johnson, who lives and works in Central Oʻahu. The name 'Wai' is the Hawaiian word for fresh water — fitting for a business built around water-efficient food systems. Being rooted in Mililani means we are close to our residential clients in Central Oʻahu and can reach any part of the island for installs and maintenance.

Hawaiʻi imports roughly 85–90% of its food. Every home and school system we install is one more source of local, pesticide-free produce that does not have to travel 2,500 miles to reach a plate. We donate all excess produce from our growing operation to local food banks and partner with community organizations to expand access to fresh food across the island. Food sovereignty is not just a selling point for us — it is the reason we started.

Yes — follow us on Instagram at @wai_gardens for growing tips, harvest photos, recipes, and behind-the-scenes looks at our installs and school programs. We also post educational content about hydroponics, aquaponics, and Oʻahu food sovereignty on Facebook. Tag us in your harvests — we love seeing what our clients are growing.

You can reach us by email at Tyler@WaiGarden.com, by phone at (808) 726-9493, or through the contact form on our website at waigarden.com/contact. We respond to all inquiries within one business day. For urgent system issues, phone is fastest. Free site evaluations can be scheduled at waigarden.com/site-evaluation.