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Aquarium Water Care & Treatment UK

Aquarium water care and treatment UK — dechlorinators, conditioners, bacteria cultures, fish medications, testing kits.

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Current Water Care & Treatment listings

Before you choose from this collection

This page collects the water conditioners and treatments we stock — dechlorinators, bacterial starters, clarifiers and remedies for aquarium and pond. Everything is dispatched from our own stock with the rest of your order.

Stable, safe water is the foundation of fishkeeping. The essentials are a dechlorinator for every water change and a bacterial starter when cycling; beyond that we carry clarifiers, pH and hardness adjusters, and targeted treatments.

Read each product's guidance and dose carefully — more is not better with water treatments. If you're diagnosing a problem, a liquid test kit tells you what's actually wrong before you reach for a remedy. Check the water-chemistry guide linked from this page.

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Frequently asked questions

Yes — UK tap water contains chlorine or chloramine that's harmless to us but toxic to fish and to the beneficial bacteria in your filter. Add a dechlorinator to every bucket of new water during water changes, or the moment you refill. It's the single most important water treatment and takes seconds to use.
Two essentials: a dechlorinator for every water change, and a bacterial starter to help cycle a new tank. A liquid test kit is the third thing worth owning. Beyond those, most treatments are for specific problems — cloudy water, pH adjustment, illness — so buy them as needed rather than dosing a healthy tank preventatively.
First identify the cause. A new tank often clouds with a harmless bacterial bloom that clears itself in a week or two. Green water is an algae issue tied to light and nutrients. A clarifier can help clump fine particles for the filter to catch, but the lasting fix is usually maturity, water changes and not overfeeding — not a bottle.
You can, with buffers and adjusters, but stability matters more than hitting a target number — most fish adapt to steady water better than to values that swing. It's usually easier to choose fish suited to your tap water than to chemically alter every change. If you do adjust, do it gradually and test as you go.
Not always — many fish medications contain copper, which is lethal to shrimp, snails and other invertebrates. Always check that a treatment is invert-safe before dosing a tank that contains them, and follow the dose exactly. When in doubt, treat affected fish in a separate hospital tank rather than the main aquarium.
Most aquarium water treatments are inexpensive — a bottle of dechlorinator or bacterial starter is a few pounds and lasts a long time, with larger pond treatments and specialist remedies costing more. Prices on this page are live: what you see is what's in stock today.

Watch: Water Care & Treatment in 60 seconds

Short clips from our own channel — the things keepers most often get wrong, answered in a minute.

Your fish died after the water change. Here's whyA neglected tank drifts acidic; one large water change then swings pH and shocks fish that had adapted. Change little and often instead.
Why your fish sink after you clean the tankFish lying on the bottom after a water change is almost always a temperature mismatch, not dirt — match the new water before it goes in.
Your tap water would kill a fish in minutesChlorine and chloramine burn gill tissue on contact. Why every bucket of tap water needs a dechlorinator before it touches the tank.
Why your water change keeps the tank cloudyWhite cloudiness in a new tank is a bacterial bloom feeding on dissolved waste, and repeated water changes prolong it.
Why white spot comes back after you treat itThe visible spot is the parasite's protected feeding stage; only the free-swimming stage is treatable, which is why courses must run their full length.
Aquarium salt is not a cure-allSalt raises salinity for every animal in the tank rather than targeting a pathogen — when it helps, when it harms, and what to use instead.
Brown aquarium water isn't dirty waterA tea-coloured tint comes from tannins released by wood and leaves, not from waste; it is harmless and many species prefer it.

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