Skip to main content
eBay Logo

Shop by category

Advanced
    • eBay Plus
    • eBay Deals
    • Find a Store
    • Help
    • Aust Post
    • Sell
    • Watch ListExpand Watch list
      Loading...
      Sign in to see your user information
    • My eBayExpand My eBay
      • My eBay Summary
      • Recently Viewed
      • Bids/Offers
      • Watch List
      • Purchase History
      • Selling/Sold
      • Saved Searches
      • Saved Sellers
      • My Garage
      • My Messages
      • Get Exclusive Savings
    • Expand cart
      Loading...
      Something went wrong. View cart for details.
    {"modules":["unloadOptimization","bandwidthDetection"],"unloadOptimization":{"browsers":{"Firefox":true,"Chrome":true}},"bandwidthDetection":{"url":"https://ir.ebaystatic.com/cr/v/c1/thirtysevens.jpg","maxViews":4,"imgSize":37,"expiry":300000,"timeout":250}}

    There seems to be a problem serving the request at this time

    You are here

    • eBay
    • Pet Supplies
    • Fish Supplies
    • Aquarium Water Tests & Treatment
    • API Aquarium Water Tests & Treatment

    API Aquarium Water Tests & Treatment

    Side Refine Panel

    Shop by Category

    • Fish
    • Water Tests & Treatment
    • Air Stones
    • Aquariums
    • Air Pumps
    • Cleaning & Maintenance
    • CO2 Equipment
    • Decorations
    • Feeders
    • Filters
    • Filter Media & Accessories
    • Food
    • Gravel & Substrate
    • Health Care
    • Heaters & Chillers
    • Lights
    • Meters & Regulators
    • Reverse Osmosis & Deionization
    • Tubing & Valves
    • UV Sterilisers
    • Water Pumps
    • Other

    Best Selling

    • API Master Freshwater Aquarium Test Kit
      API Master Freshwater Aquarium Test Kit
      4.9 out of 5 stars (338)Total ratings 338
      AU $66.00 New
      AU $20.00 Used
    • API AAP169D-38_4800 Algae Control Solution - 64Oz.
      API AAP169D-38_4800 Algae Control Solution - 64Oz.
      4.8 out of 5 stars (30)Total ratings 30
      AU $88.00 New
    • API Melafix Water Conditioner - 473ml
      API Melafix Water Conditioner - 473ml
      4.8 out of 5 stars (24)Total ratings 24
      AU $34.00 New
    • API Stress Coat+ Water Conditioner - 946ml
      API Stress Coat+ Water Conditioner - 946ml
      4.8 out of 5 stars (15)Total ratings 15
      AU $49.00 New
    • API Tapwater Conditioner - 4L
      API Tapwater Conditioner - 4L
      4.9 out of 5 stars (8)Total ratings 8
      AU $105.00 New
    • Aquarium Aquatic Fish Tank Bio API Stress Zyme 473ml
      Aquarium Aquatic Fish Tank Bio API Stress Zyme 473ml
      4.9 out of 5 stars (30)Total ratings 30
      AU $33.69 New
    • API Stress Coat Aquarium Water Conditioner - 1.89L
      API Stress Coat Aquarium Water Conditioner - 1.89L
      5 out of 5 stars (10)Total ratings 10
      AU $80.00 New
    • API Stress Zyme Bacterial Cleaner - 946ml
      API Stress Zyme Bacterial Cleaner - 946ml
      4.9 out of 5 stars (7)Total ratings 7
      AU $64.00 New
    • All

    • Auction

    • Buy It Now

    • Best Match
    • Time: ending soonest
    • Time: newly listed
    • Price + postage: lowest first
    • Price + postage: highest first
    • Lowest price
    • Highest price
    • Distance: nearest first
    • List view

    844 results

    • Brand: API - Remove filter
      • API filter applied
      • Fresh
      • All Water Types
      • Chlorine
      • Bacteria
      • Salt
      • Test Kit
      • Water Conditioner
      • Plant Fertilizer
      • All Listings filter applied
    • API Master Freshwater Aquarium Test Kit pH Nitrite Nitrate Ammonia ExP 2026
      SPONSORED

      API Master Freshwater Aquarium Test Kit pH Nitrite Nitrate Ammonia ExP 2026

      5 out of 5 stars (338)338 product ratings - API Master Freshwater Aquarium Test Kit pH Nitrite Nitrate Ammonia ExP 2026
      AU $66.00
      Free postage
      189 sold
    • API Stress Coat 946ml Aquarium Tap Water Conditioner EXP 2024
      SPONSORED

      API Stress Coat 946ml Aquarium Tap Water Conditioner EXP 2024

      5 out of 5 stars (15)15 product ratings - API Stress Coat 946ml Aquarium Tap Water Conditioner EXP 2024
      AU $50.00
      Free postage
      963 sold
    • API Master Freshwater Aquarium Test Kit pH Nitrite Nitrate Ammonia EXP 2026

      API Master Freshwater Aquarium Test Kit pH Nitrite Nitrate Ammonia EXP 2026

      5 out of 5 stars (338)338 product ratings - API Master Freshwater Aquarium Test Kit pH Nitrite Nitrate Ammonia EXP 2026
      AU $67.00
      Free postage
      189 sold
    • API AlgaeFix Pond Care Green Water Algae Fix Remover Aquarium 1.89 Litres EX2026

      API AlgaeFix Pond Care Green Water Algae Fix Remover Aquarium 1.89 Litres EX2026

      5 out of 5 stars (30)30 product ratings - API AlgaeFix Pond Care Green Water Algae Fix Remover Aquarium 1.89 Litres EX2026
      AU $88.00
      Free postage
      1,480 sold
    • API Melafix Water Conditioner - 473ml

      API Melafix Water Conditioner - 473ml

      5 out of 5 stars (24)24 product ratings - API Melafix Water Conditioner - 473ml
      AU $34.00
      Free postage
    • API Stress Zyme 946ml Aquarium Biological Water Additive EXP2026

      API Stress Zyme 946ml Aquarium Biological Water Additive EXP2026

      5 out of 5 stars (7)7 product ratings - API Stress Zyme 946ml Aquarium Biological Water Additive EXP2026
      AU $64.00
      Free postage
      423 sold
    • API Leaf Zone Aquarium Plant Fertiliser Food 473ml

      API Leaf Zone Aquarium Plant Fertiliser Food 473ml

      AU $32.00
      Free postage
    • API Tap Water Conditioner 946ml Aquarium Chlorine Remover EXP2026

      API Tap Water Conditioner 946ml Aquarium Chlorine Remover EXP2026

      5 out of 5 stars (13)13 product ratings - API Tap Water Conditioner 946ml Aquarium Chlorine Remover EXP2026
      AU $46.00
      Free postage
      817 sold
    • API Melafix Pond Melafix 473ml

      API Melafix Pond Melafix 473ml

      AU $37.00
      Free postage
    • API Aquarium Salt for Freshwater, Black, 16 oz

      API Aquarium Salt for Freshwater, Black, 16 oz

      AU $9.85
      Free postage
      or Best Offer
      Only 1 left!
    • API Stress Zyme 592ml Aquarium Biological Water Additive EXP2024

      API Stress Zyme 592ml Aquarium Biological Water Additive EXP2024

      5 out of 5 stars (30)30 product ratings - API Stress Zyme 592ml Aquarium Biological Water Additive EXP2024
      AU $37.00
      Free postage
      220 sold
    • API Stress Coat 473ml Aquarium Tap Water Conditioner EXP 2024

      API Stress Coat 473ml Aquarium Tap Water Conditioner EXP 2024

      AU $30.50
      Free postage
      316 sold
    • API Algaefix 118ml
      SPONSORED

      API Algaefix 118ml

      AU $24.99
      Free postage
    • API Accu Clear 118ml
      SPONSORED

      API Accu Clear 118ml

      AU $20.99
      Free postage
    • API Accu Clear 237ml
      SPONSORED

      API Accu Clear 237ml

      AU $32.99
      Free postage
      or Best Offer
    • Aqua One Marine Saltwater 5 in 1 Master Test Kit Aquarium Salt Water Tester

      Aqua One Marine Saltwater 5 in 1 Master Test Kit Aquarium Salt Water Tester

      AU $50.96
      Free postage
      47 sold
    • 3 x API Glass Test Tube with Caps for Aquarium Test Kit Testing Water Fish Tubes

      3 x API Glass Test Tube with Caps for Aquarium Test Kit Testing Water Fish Tubes

      AU $17.95
      Free postage
      569 sold
    • API Stress Coat 1.89L

      API Stress Coat 1.89L

      5 out of 5 stars (10)10 product ratings - API Stress Coat 1.89L
      AU $80.00
      Free postage
    • API Quick Start 473ml

      API Quick Start 473ml

      AU $47.00
      Free postage
    • API Stress Coat 30ml 118ml 237ml 592ml Water Conditioner Fish Tank Aquarium

      API Stress Coat 30ml 118ml 237ml 592ml Water Conditioner Fish Tank Aquarium

      AU $14.80 to AU $36.00
    • API Pimafix - 473ml

      API Pimafix - 473ml

      5 out of 5 stars (6)6 product ratings - API Pimafix - 473ml
      AU $29.00
      Free postage
    • API Nitra Zorb Aquarium Water Nitrate NitraZorb Removal Size 6

      API Nitra Zorb Aquarium Water Nitrate NitraZorb Removal Size 6

      AU $39.00
      Free postage
    • API GH/KH Aquarium Test Kit Fish Tank General Hardness and Carbonate Hardness

      API GH/KH Aquarium Test Kit Fish Tank General Hardness and Carbonate Hardness

      4.5 out of 5 stars (32)32 product ratings - API GH/KH Aquarium Test Kit Fish Tank General Hardness and Carbonate Hardness
      AU $32.89
      Free postage
      Only 3 left
    • API Root Tabs + Iron 10 Pack  Aquarium Plant Food Tablets - Fish Tank Fertiliser

      API Root Tabs + Iron 10 Pack Aquarium Plant Food Tablets - Fish Tank Fertiliser

      5 out of 5 stars (7)7 product ratings - API Root Tabs + Iron 10 Pack Aquarium Plant Food Tablets - Fish Tank Fertiliser
      AU $20.50
      Free postage
      Only 2 left
    • API Quick Start 30ml 118ml 237ml 473ml Bacteria Instant New Fish Tank Aquarium

      API Quick Start 30ml 118ml 237ml 473ml Bacteria Instant New Fish Tank Aquarium

      AU $17.80 to AU $52.00
      Free postage
    • API pH Proper 7.0 Powder Jar 250gm
      SPONSORED

      API pH Proper 7.0 Powder Jar 250gm

      AU $34.99
      Free postage
    • API Algaefix 237ml
      SPONSORED

      API Algaefix 237ml

      AU $34.99
      Free postage
    • API Tapwater Conditioner 30ml
      SPONSORED

      API Tapwater Conditioner 30ml

      AU $14.99
      Free postage
    • API Nitrate Test Kit Fresh/Saltwater
      SPONSORED

      API Nitrate Test Kit Fresh/Saltwater

      AU $38.99
      Free postage
    • API Melafix 118ml Fish Medicine Anti Bacterial Natural Disease Prevention

      API Melafix 118ml Fish Medicine Anti Bacterial Natural Disease Prevention

      3.5 out of 5 stars (8)8 product ratings - API Melafix 118ml Fish Medicine Anti Bacterial Natural Disease Prevention
      AU $22.00
      Free postage
      190 sold
    • API Stress Coat+ 946ml

      API Stress Coat+ 946ml

      5 out of 5 stars (15)15 product ratings - API Stress Coat+ 946ml
      AU $49.00
      Free postage
    • API Quick Start 946ml Aquarium New Tank Biological Water Additive EXP 08/2023

      API Quick Start 946ml Aquarium New Tank Biological Water Additive EXP 08/2023

      4.5 out of 5 stars (4)4 product ratings - API Quick Start 946ml Aquarium New Tank Biological Water Additive EXP 08/2023
      AU $88.00
      Free postage
      219 sold
    • API Stress Coat 473ml EXP 2024

      API Stress Coat 473ml EXP 2024

      AU $29.00
      Free postage
    • API Melafix and Pimafix 473ml

      API Melafix and Pimafix 473ml

      AU $64.00
      Free postage
    • API Leaf Zone 237ml
      SPONSORED

      API Leaf Zone 237ml

      AU $27.99
      Free postage
    • API Pond Care Chlorine & Heavy Metal Detoxifier 473ml
      SPONSORED

      API Pond Care Chlorine & Heavy Metal Detoxifier 473ml

      AU $49.99
      Free postage
    • API Ammo Lock 473ml

      API Ammo Lock 473ml

      AU $32.00
      Free postage
    • API Tap Water Conditioner For Fish Aquarium 118ml

      API Tap Water Conditioner For Fish Aquarium 118ml

      5 out of 5 stars (2)2 product ratings - API Tap Water Conditioner For Fish Aquarium 118ml
      AU $18.74
      Free postage
      Only 3 left
    • API Quick Start 473ml Aquarium New Tank Biological Water Additive EXP 2024

      API Quick Start 473ml Aquarium New Tank Biological Water Additive EXP 2024

      AU $49.00
      Free postage
      138 sold
    • API Pond Care Eco Fix 1.89L Pond Cleaner EcoFix EXP2026

      API Pond Care Eco Fix 1.89L Pond Cleaner EcoFix EXP2026

      4.5 out of 5 stars (7)7 product ratings - API Pond Care Eco Fix 1.89L Pond Cleaner EcoFix EXP2026
      AU $94.00
      Free postage
      128 sold
    • API Tap Water Conditioner 3.8L Aquarium Chlorine Remover EXP2025

      API Tap Water Conditioner 3.8L Aquarium Chlorine Remover EXP2025

      5 out of 5 stars (8)8 product ratings - API Tap Water Conditioner 3.8L Aquarium Chlorine Remover EXP2025
      AU $105.00
      Free postage
      246 sold
    • API Algaefix 118ml 237ml Algae Remover Algaecide Aquarium  Fish Tank

      API Algaefix 118ml 237ml Algae Remover Algaecide Aquarium Fish Tank

      AU $23.85 to AU $33.00
    • API PH Up 473ml Professional Raise PH in Fish Aquarium Water EXP 2023

      API PH Up 473ml Professional Raise PH in Fish Aquarium Water EXP 2023

      4 out of 5 stars (4)4 product ratings - API PH Up 473ml Professional Raise PH in Fish Aquarium Water EXP 2023
      AU $38.50
      Free postage
      80 sold

    Results pagination - page 1

    1. 1
    2. 2
    3. 3
    4. 4
    5. 5
    6. 6
    7. 7
    8. 8
    9. 9
    10. 10

    Top Rated

    See all- Top Rated
    • API Master Freshwater Aquarium Test Kit
      API Master Freshwater Aquarium Test Kit
      4.9 out of 5 stars (338)Total ratings 338
      99% agree - Would recommend
      AU $66.00 New
      AU $20.00 Used
    • Aquarium Aquatic Fish Tank Bio API Stress Zyme 473ml
      Aquarium Aquatic Fish Tank Bio API Stress Zyme 473ml
      4.9 out of 5 stars (30)Total ratings 30
      100% agree - Would recommend
      AU $33.69 New
    • API AAP169D-38_4800 Algae Control Solution - 64Oz.
      API AAP169D-38_4800 Algae Control Solution - 64Oz.
      4.8 out of 5 stars (30)Total ratings 30
      100% agree - Would recommend
      AU $88.00 New
    • API Melafix Water Conditioner - 473ml
      API Melafix Water Conditioner - 473ml
      4.8 out of 5 stars (24)Total ratings 24
      100% agree - Would recommend
      AU $34.00 New
    • API Stress Coat+ Water Conditioner - 946ml
      API Stress Coat+ Water Conditioner - 946ml
      4.8 out of 5 stars (15)Total ratings 15
      100% agree - Would recommend
      AU $49.00 New
    • API (AP052Q) Tap Water Conditioner 32oz - (0317163170526)
      API (AP052Q) Tap Water Conditioner 32oz - (0317163170526)
      4.9 out of 5 stars (13)Total ratings 13
      100% agree - Would recommend
      AU $46.00 New
    • API PondCare Pond Master Test Kit Liquid Water Conditioner
      API PondCare Pond Master Test Kit Liquid Water Conditioner
      5 out of 5 stars (11)Total ratings 11
      100% agree - Would recommend
      AU $59.00 New
    • API LR1800 Nitrate Test Kit
      API LR1800 Nitrate Test Kit
      4.9 out of 5 stars (10)Total ratings 10
      100% agree - Would recommend
      AU $29.99 New
    You may also like
    Slide {current_page} of {total_pages} - You may also like
    • Seachem Aquarium Water Tests & Treatment

    • Marine Aquariums

    • Aquarium Water Tests & Treatment

    • API Aquarium Water Test Kits

    • API Aquarium Water Conditioners

    Additional site navigation

    • About eBay
    • Announcements
    • Community
    • Media Centre
    • Seller Centre
    • Policies
    • Advertise
    • Help
    • Site Map
    Copyright © 1995-2022 eBay Inc. All Rights Reserved. User Agreement, Privacy, Cookies and AdChoiceNorton Secured - powered by DigiCert