Water Conditioners & Test Kits

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Stella & Chewy's Shredrs chicken and chicken liver wet dog food pouch shown from the front.
Stella & Chewy's

Stella & Chewy's Shredded Wet Dog Food, Chicken & Chicken Liver in Broth, 79 g Pouch

Stella & Chewy's Shredrs Cage Free Chicken & Chicken Liver Recipe in Broth is wet dog food for a complete and balanced meal or a topper, in a 2.8 oz (79 g) pouch. Real shredded muscle meat in slowly simmered broth — adds protein...
£20.36
£20.36
Preferhouse dog shirt shown from the front with its striped design.
Preferhouse

Preferhouse Striped Dog T-Shirts for Summer, XS–XL, Soft Quick-Dry Fabric

Preferhouse striped dog T-shirts are pet tops for summer wear and everyday outings, offered in five sizes from XS to XL with stripe and heart-pattern designs. Five sizes, XS to XL — options for small, medium, and large dogs, with a size chart to...
£21.15
£21.15
Bbmmayy Rhinestone Dog Collar shown from the front in dark blue.
Bbmmayy

Bbmmayy Rhinestone Dog Collar, Dark Blue Size S with Flower Detail and Adjustable Fit

Bbmmayy Rhinestone Dog Collar is a decorative dog collar designed to dress up your dog, with a dark blue size S fit for necks measuring 10.6–13 in (26–32 cm) and an adjustable metal buckle. Dark blue, size S fits necks 10.6–13 in (26–32 cm)...
£21.26
£21.26
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  • Seachem Reef Phytoplankton product packaging shown from the front.
    Seachem

    Seachem Reef Phytoplankton Marine Aquarium Feed, 4 L Concentrate

    Seachem Reef Phytoplankton is a concentrated marine aquarium feed for tropical filter feeders and invertebrates, made with green and brown phytoplankton sized from 1–20 μm. Green and brown marine phytoplankton — provides a mixed-culture feed. Particles from 1–20 μm — serves a broad range...
    £129.70
    £129.70
  • WLR Industries Hanna HI772-26 reagents shown as replacement packets for marine alkalinity testing.
    WLR Industries

    WLR Industries HI772 Marine Alkalinity Reagents, 2 Pack, 50 Tests

    WLR Industries Hanna HI772-26 is a two-pack of pre-made replacement reagents for measuring marine alkalinity (dKH) with the HI772 Checker, supplied as a 50-test pack. Made for the HI772 Marine Alkalinity Checker — provides replacement reagents for its dKH testing. Pre-made reagent packets —...
    £71.29
    £71.29
  • D-D Rowaphos phosphate remover shown from the front.
    d/d

    D-D Rowaphos Aquarium Phosphate Remover, 1000ml Non-Leaching Media

    D-D Rowaphos is a 1000ml phosphate-removal media for marine and reef aquariums, designed to remove phosphate without leaching it back into the water. Made for marine and reef aquariums — focuses phosphate removal on these aquarium types. 1000ml container — provides a clearly stated...
    £88.67
    £88.67
  • ESV Aquatics B-Ionic Calcium Buffer System shown from the front.
    ESV Aquatics

    ESV Aquatics B-Ionic Calcium Buffer System, 3.8 L 2-Pack for Reef Aquariums

    ESV Aquatics B-Ionic Calcium Buffer System is a two-part liquid supplement for maintaining calcium and alkalinity in saltwater aquariums, supplied as two concentrated 1-gallon (3.785 L) bottles. Two liquid components used in equal volumes — supports aquarium maintenance without mixing powders. Concentrated calcium and...
    £101.56
    £101.56
  • Brightwell Aquatics Reef Snow product shown from the front.
    Brightwell Aquatics

    Brightwell Aquatics Reef Snow Coral & Invertebrate Food, 2L Marine Formula

    Brightwell Aquatics Reef Snow is a 2L marine food supplement designed to nourish corals and suspension-feeding invertebrates with carbonate-bound elements, marine-derived proteins and lipids. Replicates natural marine snow with organic and inorganic nutrients — supports coral tissue and skeletal development. Provides major, minor and...
    £100.73
    £100.73
  • Seachem Cichlid Lake Salt package shown from the front.
    Seachem

    Seachem Cichlid Lake Salt, 4 kg – Rift Lake Mineral Blend for African Cichlids

    Seachem Cichlid Lake Salt is a mineral salt blend for replicating the natural water environment of Rift Lake African cichlids, supplied in a 4 kg / 8.8 lbs size. Calcium, magnesium, sodium, and potassium — provides the physiologically essential elements named in the formula....
    £117.28
    £117.28
  • Anbachi digital salinity meter shown from the front.
    Anbachi

    Anbachi 3-in-1 Digital Salinity Meter with ATC and Backlit LCD

    Anbachi’s 3-in-1 Digital Salinity Meter is a pen-style water tester for measuring specific gravity, salinity and temperature in aquariums, pools, hydroponics and other water-testing settings. Specific gravity range of 1.000–1.045, salinity range of 0–55 ppt and temperature range of 1–99 °C — read three...
    £72.47
    £72.47
  • Seachem Safe conditioner shown from the front with its product packaging.
    Seachem

    Seachem Safe Aquarium Water Conditioner, 4 kg Dry Concentrate for Freshwater & Saltwater

    Seachem Safe is a concentrated dry water conditioner for freshwater and saltwater aquariums, supplied in a 4 kg (8.8 lbs) size for treating aquarium water. Removes chlorine, chloramine and ammonia — conditions water for aquarium use. Converts ammonia to a non-toxic form — makes...
    £185.36
    £185.36
  • THE 2HR AQUARIST aquarium fertilizer APT 1/ Zero bottle shown from the front.
    THE 2HR AQUARIST

    THE 2HR AQUARIST Aquarium Plant Fertiliser APT 1/ Zero, 1000ml, Zero Nitrates and Phosphates

    THE 2HR AQUARIST APT 1/ Zero is an all-in-one planted aquarium fertilizer for tanks with more fish, combining macro and micro nutrients in a 1000 ml (33.8 fl oz) bottle. Made for planted aquariums with more fish — adds an all-in-one fertilizer option to...
    £90.93
    £90.93
  • Red Sea Reef Energy Plus bottle shown from the front.
    Red Sea

    Red Sea Reef Energy Plus Coral Food, 1000 ml AB+ All-in-One Formula for Reef Tanks

    Red Sea Reef Energy Plus is a 1000 ml all-in-one coral food for saltwater reef aquariums, made for soft, LPS, SPS, and non-photosynthetic corals. Long-term laboratory testing showed 15% faster coral growth than the original two-part formula — a measured growth comparison. Combined all-in-one...
    £86.96
    £86.96
  • THE 2HR AQUARIST APT 3 / Complete aquarium fertilizer shown from the front.
    THE 2HR AQUARIST

    THE 2HR AQUARIST Aquarium Plant Fertiliser APT 3 / Complete, 1000ml All-in-One Formula

    THE 2HR AQUARIST APT 3 / Complete is an all-in-one planted aquarium fertilizer for supporting aquatic plant growth, combining comprehensive macro NPK with micro iron, magnesium and trace minerals in a 1000ml size. Macro NPK plus iron, magnesium and trace minerals — brings key...
    £90.93
    £90.93
  • DrTim's Aquatics One & Only Saltwater package shown from the front.
    DrTim's Aquatics

    DrTim's Aquatics One & Only Saltwater Aquarium Treatment, 237 ml for Biofilter Support

    DrTim's Aquatics One & Only Saltwater is an aquarium treatment designed to convert waste into a non-toxic form and establish a biofilter in saltwater tanks; this listing is the 8 oz size. Creates a biofilter — helps remove toxic ammonia and nitrite naturally. For...
    £74.55
    £74.55
  • Seachem Reef Phytoplankton container shown from the front.
    Seachem

    Seachem Reef Phytoplankton 2 L Marine Aquarium Food for Invertebrates

    Seachem Reef Phytoplankton is a concentrated marine aquarium food for tropical filter feeders and invertebrates, made from green and brown phytoplankton sized 1–20 µm. Provides essential fatty acids, proteins, vitamins, amino acids and natural carotenoids — a broad range of nutrients for invertebrate diets....
    £88.71
    £88.71
  • Brightwell Aquatics CoralAmino reef supplement bottle shown from the front.
    Brightwell Aquatics

    Brightwell Aquatics CoralAmino Coral Amino Acid Reef Supplement, 2 L for Coral Growth and Colouration

    Brightwell Aquatics CoralAmino is a 2 L marine reef amino acid supplement formulated to support aquarium coral nutrition, tissue growth and coloration. Free-form amino acids modeled on stony coral tissue ratios — provides amino acid building blocks for coral tissue. Formulated to support tissue...
    £178.63
    £178.63
  • ATI ICP Lab Analysis Pro test kit shown from the front.
    ATI

    ATI Reef Aquarium Water Test Kit, 1 Test, ICP Lab Analysis Pro with RO/DI Testing

    ATI ICP Lab Analysis Pro is a laboratory water test kit for reef aquarium monitoring, combining the full Standard analysis with nitrate, fluoride, carbonate hardness (KH), and RO/DI water analysis. Full Standard analysis plus nitrate, fluoride, KH, and RO/DI water analysis — gives you...
    £72.43
    £72.43
  • Red Sea reef-care dosing system shown from the front.
    Red Sea

    Red Sea Reef Care Supplement Dosing System, Medium 303 L, 4-Part for Mixed Reefs

    Red Sea RCP Complete Reef Care is a four-part supplement dosing system designed to support coral growth in 80-gallon (303 L) saltwater mixed reef aquariums. Four-part dosing system — gives the product its defined supplement format. Medium size for an 80-gallon (303 L) aquarium...
    £197.22
    £197.22
  • Seachem Clarity water clarifier shown from the front.
    Seachem

    Seachem Clarity Aquarium Water Clarifier, 4 L for Freshwater and Marine Tanks

    Seachem Clarity is a water clarifier designed to clear cloudy water in freshwater and saltwater aquariums, in a 4 L / 1 fl gal size. For freshwater and marine aquariums — one clarifier serves both water environments. Designed to clear all types of clouding...
    £129.19
    £129.19
  • Seachem Flourish Nitrogen container shown from the front.
    Seachem

    Seachem Flourish Nitrogen Aquarium Plant Supplement, 4 L, Concentrated Nitrate and Ammonium

    Seachem Flourish Nitrogen is a concentrated nitrogen supplement for planted aquariums, supplied in a 4 L / 1 fl gal container with a 15,000 mg/L blend of nitrogen sources. 15,000 mg/L nitrogen-source blend — provides concentrated nitrogen supplementation for aquarium plants. Nitrate and plant-preferred...
    £132.61
    £132.61
  • DrTim's Aquatics One and Only Reef shown from the front.
    DrTim's Aquatics

    DrTim's Aquatics One & Only Reef Aquarium Treatment, 237 ml Biofilter Support

    DrTim's Aquatics One and Only Reef is an aquarium treatment designed to convert waste into a non-toxic form in reef, nano and seahorse tanks; this 8 fl oz (237 mL) size helps establish a biofilter. For reef, nano and seahorse aquariums — made for...
    £70.11
    £70.11
  • Seachem Flourish Advance growth supplement shown from the front of its packaging.
    Seachem

    Seachem Flourish Advance Aquatic Plant Growth Supplement, 2 L, Root and Shoot Support

    Seachem Flourish Advance is an aquatic plant growth supplement designed to stimulate root and shoot development, supplied in a 2 L (67.6 fl. oz.) size for regular aquarium use. Phytohormones, minerals and nutrients — support growth in aquatic plant roots and shoots. A 10–14...
    £91.80
    £91.80
  • Fritz Aquatics Fritz Complete water conditioner bottle shown from the front.
    Fritz Aquatics

    Fritz Aquatics Complete Aquarium Water Conditioner, 3.8 L, Freshwater & Saltwater Dechlorinator

    Fritz Aquatics Fritz Complete is a concentrated, one-step aquarium water conditioner for fresh and saltwater, supplied in a 1 U.S. gal (3.8 L) size and dosed at 1 tsp (5 mL) per 50 U.S. gallons (189 L). Neutralizes chlorine, chloramines and heavy metals, and...
    £132.33
    £132.33
  • Brightwell Aquatics Phosphāt-E phosphate remover bottle shown from the front.
    Brightwell Aquatics

    Brightwell Aquatics Phosphāt-E Liquid Phosphate Remover, 500 mL for Aquariums

    Brightwell Aquatics Phosphāt-E is a liquid phosphate remover for marine, reef and freshwater aquariums, supplied in a 500 mL bottle for managing reactive phosphate. Works on reactive phosphate after application — supports phosphate control in aquarium water. Maximum daily dose of 2.5 mL per...
    £67.93
    £67.93
  • EcoBio-Block Aquarium Water Clarifier Medium two-pack shown from the front.
    EcoBio-Block

    EcoBio-Block Aquarium Water Clarifier, Medium 2-Pack for 56.8–151 L Tanks

    EcoBio-Block Aquarium Water Clarifier is a two-stone freshwater aquarium treatment for helping clear cloudy water and stabilize water chemistry, with each Medium stone treating 15–40 gallons (57–151 L). Two porous volcanic-rock stones with mineral nutrients and a neutralizing cement binder — help absorb water-quality...
    £81.24
    £81.24
  • Brightwell Aquatics MicroBacter Start XLM product shown from the front.
    Brightwell Aquatics

    Brightwell Aquatics MicroBacter Start XLM Marine Aquarium Cycling Aid, 20L, 15x Concentrated

    Brightwell Aquatics MicroBacter Start XLM is a concentrated live-microbe cycling aid for establishing or restoring biological filtration in marine aquariums, with a 15x-strength formula in the 20L size. 15x-concentrated blend — supports biological filtration with a concentrated dose of beneficial microbes. Usually cycles a...
    £1,174.99
    £1,174.99

Dechlorinators, bacteria starters, test kits, thermometers and hydrometers for keeping an eye on water quality. You will find pieces from Seachem, Brightwell Aquatics, DrTim's Aquatics and 89 more. Useful things to check include reef aquarium, filter media and saltwater tanks.

Smaller collections inside: Water Treatments & Conditioners, Aquarium Test Kits & Thermometers.

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Questions about Water Conditioners & Test Kits

Who makes the products in Water Conditioners & Test Kits?

Water Conditioners & Test Kits brings together Seachem, Brightwell Aquatics, DrTim's Aquatics and 89 other makers.

What does Water Conditioners & Test Kits cover?

There are separate pages for Water Treatments & Conditioners and Aquarium Test Kits & Thermometers. On each one, filters narrow things down by brand and price.

How much does delivery cost on Water Conditioners & Test Kits?

Nothing. Delivery to any UK address is free, however small the order. We prepare orders within 1–3 working days; after that, most parcels reach you within 3–7 working days, and a tracking link is emailed as soon as yours is on its way. Some Highlands and island postcodes and Northern Ireland can take a little longer.

Can I send back something from Water Conditioners & Test Kits?

Send it back within 30 days of delivery, for any reason, as long as it is unused and still in its original packaging. We email a prepaid label so the return costs you nothing, and the money goes back to the way you paid no later than 10 working days after the parcel reaches us.

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