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    • Pet Supplies
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    • Aquarium CO2 Equipment

    Aquarium CO2 Equipment

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    • Complete CO2 System

      Complete CO2 System

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      CO2 Diffuser

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      CO2 Cylinder

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    Best selling

    See all- Best selling
    • ISTA I-517 CO2 Cylinder - 3 Pack
      ISTA I-517 CO2 Cylinder - 3 Pack
      4.9 out of 5 stars (26)Total ratings 26
      £15.99 New
    • ISTA CO2 Diffuser Set (I-512)
      ISTA CO2 Diffuser Set (I-512)
      4.4 out of 5 stars (14)Total ratings 14
      £8.99 New
    • Fluval Pressurised Co2 System Kit 88g Fish Tank
      Fluval Pressurised Co2 System Kit 88g Fish Tank
      4.4 out of 5 stars (12)Total ratings 12
      £69.99 New
    • Fluval Co2 Pressurised Kit - 45g
      Fluval Co2 Pressurised Kit - 45g
      4.2 out of 5 stars (10)Total ratings 10
      £42.95 New
    • Fluval Planted Aquarium Fish Tank Pressurised Co2 Kit - 17557
      Fluval Planted Aquarium Fish Tank Pressurised Co2 Kit - 17557
      3.9 out of 5 stars (8)Total ratings 8
      £45.00 New
      £30.00 Used
    • Colombo Co2 Reactor Set 2.3l - Helps Aquarium Plants Grow
      Colombo Co2 Reactor Set 2.3l - Helps Aquarium Plants Grow
      4.5 out of 5 stars (2)Total ratings 2
      £170.00 New
    • Fluval Co2 Indicator Kit A7551 Aquarium Fish Tank Planted Plants
      Fluval Co2 Indicator Kit A7551 Aquarium Fish Tank Planted Plants
      3.8 out of 5 stars (4)Total ratings 4
      £9.99 New
    • All

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    9,564 results

      • CO2 Diffuser
      • Bubble Counter
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      • Fluval
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    • Co2 Fire Extinguisher! 2kg & 5kg! Fish Tanks / Aquariums! FREE NEXT DAY DELIVERY
      SPONSORED

      Co2 Fire Extinguisher! 2kg & 5kg! Fish Tanks / Aquariums! FREE NEXT DAY DELIVERY

      £20.00 to £500.00
      Click & Collect
      385 sold
    • Ista CO2 Disposable Can x3 Pack Planted Plant Fish Tank Aquascaping Aquarium
      SPONSORED

      Ista CO2 Disposable Can x3 Pack Planted Plant Fish Tank Aquascaping Aquarium

      5 out of 5 stars (26)26 product ratings - Ista CO2 Disposable Can x3 Pack Planted Plant Fish Tank Aquascaping Aquarium
      £16.45
      Click & Collect
      Free postage
    • Fish Tank Aquarium Plant CO2 Diffuser Bubble Atomizer Solenoid Regulat KY
      SPONSORED

      Fish Tank Aquarium Plant CO2 Diffuser Bubble Atomizer Solenoid Regulat KY

      £7.67
      Free postage
      or Best Offer
    • aquarium co2 regulator

      aquarium co2 regulator

      £50.00
      0 bids
      £8.00 postage
      Ending Friday at 12:34PM BST20h 23m
      or Best Offer
      Click & Collect
    • Co2Art Aquarium Glass Co2 Drop Checker and Solution Kit

      Co2Art Aquarium Glass Co2 Drop Checker and Solution Kit

      4.5 out of 5 stars (2)2 product ratings - Co2Art Aquarium Glass Co2 Drop Checker and Solution Kit
      £10.00
      £3.35 postage
      or Best Offer
    • Fish & Aquarium DIY CO2 System Generator Reactor Kit Pressure Gauge Bottle Cap

      Fish & Aquarium DIY CO2 System Generator Reactor Kit Pressure Gauge Bottle Cap

      £15.99
      Click & Collect
      90 sold
    • JBL Co2 System m500 refillable aquascape

      JBL Co2 System m500 refillable aquascape

      £40.00
      0 bids
      £9.00 postage
      Ending Sunday at 12:35PM BST2d 20h
      or Buy it now
    • Co2 Art PRO-SE Series - Aquarium CO2 Dual Stage Regulator FREE 3M CLEAR TUBING

      Co2 Art PRO-SE Series - Aquarium CO2 Dual Stage Regulator FREE 3M CLEAR TUBING

      £95.00
      £4.45 postage
      or Best Offer
    • Aquarium CO2 System (bioplast) with Adjustable Pressure for Planted Tank

      Aquarium CO2 System (bioplast) with Adjustable Pressure for Planted Tank

      £5.00
      0 bids
      £8.00 postage
      Ending 23 May at 1:07PM BST3d 20h
      or Best Offer
      Click & Collect
    • Stainless Steel CO2 Non-Return Check Valve For Aquarium , Fish Tank

      Stainless Steel CO2 Non-Return Check Valve For Aquarium , Fish Tank

      £4.60 to £7.20
      631 sold
    • ISTA WATERPLANT CO2 DIFFUSER SET SYSTEM GROWING LIVE FISH TANK AQUARIUM PLANTS

      ISTA WATERPLANT CO2 DIFFUSER SET SYSTEM GROWING LIVE FISH TANK AQUARIUM PLANTS

      4.5 out of 5 stars (14)14 product ratings - ISTA WATERPLANT CO2 DIFFUSER SET SYSTEM GROWING LIVE FISH TANK AQUARIUM PLANTS
      £13.70
      Click & Collect
      Free postage
      916 sold
    • Aquarium Fish Tank Check Valve Bubble Counter For CO2 Regulator Valve UK

      Aquarium Fish Tank Check Valve Bubble Counter For CO2 Regulator Valve UK

      £4.95
      Free postage
    • Aquarium CO2 Regulator Dual Gauge Pressure System w/Bubble Counter & Check Valve

      Aquarium CO2 Regulator Dual Gauge Pressure System w/Bubble Counter & Check Valve

      £32.99
    • NEW Aquarium CO2 Diffuser Fish Tank Bubble Atomizer Reactor Solenoid Regulator
      SPONSORED

      NEW Aquarium CO2 Diffuser Fish Tank Bubble Atomizer Reactor Solenoid Regulator

      £16.33
      Free postage
      or Best Offer
      5 watching
    • Stainless Steel Multi Way Aquarium CO2 Splitter Distributor Solenoid Check Valve
      SPONSORED

      Stainless Steel Multi Way Aquarium CO2 Splitter Distributor Solenoid Check Valve

      £32.67 to £64.11
      Free postage
      3 watching
    • TETRA * CO2 OPTIMAT COMPLETE KIT FOR TROPICAL AQUARIUM FREE DELIVERY PLANTS
      SPONSORED

      TETRA * CO2 OPTIMAT COMPLETE KIT FOR TROPICAL AQUARIUM FREE DELIVERY PLANTS

      £21.28
      Click & Collect
      29 sold
    • Fluval CO2 45g / 95g Kits & Spares Plant Growth Health Aquarium Fish Tank

      Fluval CO2 45g / 95g Kits & Spares Plant Growth Health Aquarium Fish Tank

      4 out of 5 stars (8)8 product ratings - Fluval CO2 45g / 95g Kits & Spares Plant Growth Health Aquarium Fish Tank
      £3.99 to £72.90
      Free postage
      70 sold
    • Tropica CO2 Diffuser with Check Valve & Bubble Counter Plant Aquarium Fish Tank

      Tropica CO2 Diffuser with Check Valve & Bubble Counter Plant Aquarium Fish Tank

      £10.95
      Click & Collect
      Free postage
      109 sold
    • Twinstar CO2 Diffuser - Like AquaRio - gas fine beaded ceramic diffusor

      Twinstar CO2 Diffuser - Like AquaRio - gas fine beaded ceramic diffusor

      £10.99 to £12.99
      Click & Collect
      Free postage
    • JBL ProFlora Bio80 - co2 System pro flora carbon aquarium fertiliser bio 80

      JBL ProFlora Bio80 - co2 System pro flora carbon aquarium fertiliser bio 80

      5 out of 5 stars (1)1 product ratings - JBL ProFlora Bio80 - co2 System pro flora carbon aquarium fertiliser bio 80
      £5.50
      4 bids
      £2.50 postage
      Ending Friday at 12:39PM BST20h 28m
    • Aquarium CO2 System (Dennerle) with Adjustable Pressure for Planted Tank

      Aquarium CO2 System (Dennerle) with Adjustable Pressure for Planted Tank

      £65.00
      Click & Collect
      £8.05 postage
    • Full 2kg CO2 for Aquarium/fish tank

      Full 2kg CO2 for Aquarium/fish tank

      £11.00
      Click & Collect
      £7.99 postage
    • NEW Fluval CO2 Ceramic Diffuser with Suction Cup for Aquariums and Tanks

      NEW Fluval CO2 Ceramic Diffuser with Suction Cup for Aquariums and Tanks

      4 out of 5 stars (5)5 product ratings - NEW Fluval CO2 Ceramic Diffuser with Suction Cup for Aquariums and Tanks
      £11.29
      Click & Collect
      Free postage
      Only 2 left
    • AQUARIUM CO2 PROFESSIONAL SYSTEM Fish Tank, 8L CO2 Bottle and aquarium set

      AQUARIUM CO2 PROFESSIONAL SYSTEM Fish Tank, 8L CO2 Bottle and aquarium set

      £169.99
    • Aquarium DIY CO2 Generator System Kit With Pressure Air Flow Adjustment Wa_k KY

      Aquarium DIY CO2 Generator System Kit With Pressure Air Flow Adjustment Wa_k KY

      £20.24 to £22.62
      Free postage
    • Fish Tank CO2 Generator Bottle Cap Aquarium Carbon Dioxide DIY Quick Screw Part

      Fish Tank CO2 Generator Bottle Cap Aquarium Carbon Dioxide DIY Quick Screw Part

      £2.26
      Was: £2.38
      Free postage
      or Best Offer
    • Fluval Aquarium Fish Tank CO2 Bubble Counter 88g

      Fluval Aquarium Fish Tank CO2 Bubble Counter 88g

      5 out of 5 stars (3)3 product ratings - Fluval Aquarium Fish Tank CO2 Bubble Counter 88g
      £3.69
      £3.95 postage
      Only 2 left
    • TETRA * CO2 DEPOT 11g // 650ml * CARBON DIOXIDE FERTILISER * PLANTS *NEW
      SPONSORED

      TETRA * CO2 DEPOT 11g // 650ml * CARBON DIOXIDE FERTILISER * PLANTS *NEW

      £15.29
      Click & Collect
    • Ista CO2 Indicator with Solution Planted Aquarium Carbon Dioxide Monitor
      SPONSORED

      Ista CO2 Indicator with Solution Planted Aquarium Carbon Dioxide Monitor

      3.5 out of 5 stars (4)4 product ratings - Ista CO2 Indicator with Solution Planted Aquarium Carbon Dioxide Monitor
      £6.99
      Click & Collect
    • Aquarium CO2 Output Pressure Regulator Dual Gauges Solenoid For Plants Fish Tank
      SPONSORED

      Aquarium CO2 Output Pressure Regulator Dual Gauges Solenoid For Plants Fish Tank

      £34.99
      or Best Offer
      43 watching
    • Ista CO2 100 Tablets Carbon Dioxide Diffuser for Freshwater Planted Aquariums
      SPONSORED

      Ista CO2 100 Tablets Carbon Dioxide Diffuser for Freshwater Planted Aquariums

      £12.49
      Click & Collect
      173 sold
    • AQUARIUM CO2 SYSTEM, Fish Tank 2L Co2 Bottle + aquarium complete set

      AQUARIUM CO2 SYSTEM, Fish Tank 2L Co2 Bottle + aquarium complete set

      £137.99 to £149.99
    • JBL ProFlora BioRefill Refill set for bio-CO2 system Aquarium Fish Tank Planted

      JBL ProFlora BioRefill Refill set for bio-CO2 system Aquarium Fish Tank Planted

      5 out of 5 stars (3)3 product ratings - JBL ProFlora BioRefill Refill set for bio-CO2 system Aquarium Fish Tank Planted
      £8.49
      Click & Collect
      4 watching
    • Fluval CO2 Pressurised Kits 45/95g & Accessories Planted Tanks Growth Health

      Fluval CO2 Pressurised Kits 45/95g & Accessories Planted Tanks Growth Health

      £4.95 to £44.95
    • Ista Replacement CO2 Diffuser Horizontal Chamber for Planted Aquarium Fish Tank

      Ista Replacement CO2 Diffuser Horizontal Chamber for Planted Aquarium Fish Tank

      5 out of 5 stars (2)2 product ratings - Ista Replacement CO2 Diffuser Horizontal Chamber for Planted Aquarium Fish Tank
      £5.99
      Click & Collect
      81 sold
    • Co2 Fish Tank Aquarium PlantSpiral Diffuser Atomizer With Bubble Counter - UK

      Co2 Fish Tank Aquarium PlantSpiral Diffuser Atomizer With Bubble Counter - UK

      £11.49
      Click & Collect
      Free postage
      or Best Offer
      130 sold
    • 2Pcs Aquarium Multifunction DIY CO2 System Kit Generator Bottle Cap Fish Tank

      2Pcs Aquarium Multifunction DIY CO2 System Kit Generator Bottle Cap Fish Tank

      £3.40
      Free postage
      or Best Offer
    • Aquarium CO2 Monitor Glass Drop Ball Tester
      SPONSORED

      Aquarium CO2 Monitor Glass Drop Ball Tester

      £3.67 to £5.44
      Free postage
    • Ista CO2 Ceramic Diffuser for Planted Aquarium Fish Tank with Suction Cup 3 Size
      SPONSORED

      Ista CO2 Ceramic Diffuser for Planted Aquarium Fish Tank with Suction Cup 3 Size

      £4.99 to £8.99
    • 3 x 3-PACKS ISTA WATERPLANT DISPOSABLE Co2 CAN BOTTLE LIVE TANK AQUARIUM PLANTS

      3 x 3-PACKS ISTA WATERPLANT DISPOSABLE Co2 CAN BOTTLE LIVE TANK AQUARIUM PLANTS

      £39.99
      Free postage
      Only 3 left
    • AQUARIUM CO2 PRECISE NEEDLE VALVE DOUBLE HEADED REGULATOR DURABLE NEW 

      AQUARIUM CO2 PRECISE NEEDLE VALVE DOUBLE HEADED REGULATOR DURABLE NEW 

      £8.99
      Click & Collect
    • Fluval Plant & Shrimp Stratum Aquarium Substrate

      Fluval Plant & Shrimp Stratum Aquarium Substrate

      4 out of 5 stars (9)9 product ratings - Fluval Plant & Shrimp Stratum Aquarium Substrate
      £9.39 to £33.69
      Click & Collect
      £3.95 postage
      73 sold
    • Aquarium Plants Cylinder CO2 Generator System Kit Carbon Dioxide Reactor Set

      Aquarium Plants Cylinder CO2 Generator System Kit Carbon Dioxide Reactor Set

      £41.75 to £56.39
      Free postage
      33 sold
    • Seachem Flourite Aquarium Fish Tank Plant Substrate

      Seachem Flourite Aquarium Fish Tank Plant Substrate

      £19.69
      Click & Collect
      £3.95 postage
    • Tropica Plant Growth System 60. Pressurised co2 for healthy live aquatic plants

      Tropica Plant Growth System 60. Pressurised co2 for healthy live aquatic plants

      5 out of 5 stars (3)3 product ratings - Tropica Plant Growth System 60. Pressurised co2 for healthy live aquatic plants
      £19.99
      Click & Collect
      Free postage
      170 sold
    • Tropica 3-in-1 CO2 Diffuser - Bubble Counter, Reflux Valve and Ceramic Diffuser

      Tropica 3-in-1 CO2 Diffuser - Bubble Counter, Reflux Valve and Ceramic Diffuser

      3.5 out of 5 stars (6)6 product ratings - Tropica 3-in-1 CO2 Diffuser - Bubble Counter, Reflux Valve and Ceramic Diffuser
      £12.13
      Click & Collect
      36 sold
    • Ista Waterplant Disposable CO2 Can x3 Pack Planted Plant Fish Tank Aquarium

      Ista Waterplant Disposable CO2 Can x3 Pack Planted Plant Fish Tank Aquarium

      5 out of 5 stars (26)26 product ratings - Ista Waterplant Disposable CO2 Can x3 Pack Planted Plant Fish Tank Aquarium
      £19.49
      Click & Collect

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    Highest-rated products

    See all- Highest-rated products
    • Supa 57031 10ft Plant Weight
      Supa 57031 10ft Plant Weight
      4.8 out of 5 stars (58)Total ratings 58
      98% agree - Would recommend
      £5.49 New
    • ISTA I-517 CO2 Cylinder - 3 Pack
      ISTA I-517 CO2 Cylinder - 3 Pack
      4.9 out of 5 stars (26)Total ratings 26
      100% agree - Would recommend
      £15.99 New
    • API LEAF ZONE Aquarium Plant Fertiliser - 473ml (576J)
      API LEAF ZONE Aquarium Plant Fertiliser - 473ml (576J)
      4.9 out of 5 stars (20)Total ratings 20
      100% agree - Would recommend
      £12.35 New
    • Fish Tank Aquarium Co2 Diffuser Check Valve U Shape Glass Tube Suction Cup Kit
      Fish Tank Aquarium Co2 Diffuser Check Valve U Shape Glass Tube Suction Cup Kit
      5 out of 5 stars (12)Total ratings 12
      100% agree - Would recommend
      £5.25 New
    • JBL Kugeln The 7 13 Balls Plant Nutrients
      JBL Kugeln The 7 13 Balls Plant Nutrients
      4.9 out of 5 stars (9)Total ratings 9
      100% agree - Would recommend
      £9.29 New
    • Fluval Plant and Shrimp Stratum - 12693
      Fluval Plant and Shrimp Stratum - 12693
      4.9 out of 5 stars (9)Total ratings 9
      87% agree - Would recommend
      £11.35 New
    • Tropica Plant Growth System 60 - 3x Refill Bottle
      Tropica Plant Growth System 60 - 3x Refill Bottle
      4.9 out of 5 stars (8)Total ratings 8
      100% agree - Would recommend
      £26.99 New
    • Evolution Aqua Plant Food Complete Liquid Aquarium Fertiliser 500ml
      Evolution Aqua Plant Food Complete Liquid Aquarium Fertiliser 500ml
      4.7 out of 5 stars (27)Total ratings 27
      96% agree - Would recommend
      £12.70 New

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