Seachem Prime Concentrated Conditioner, 500 ml

Overview

This 500ml bottle neutralises chlorine and chloramine from tap water and helps reduce nitrites and nitrates, making it a mainstay for anyone setting up or maintaining a tank. It is highly concentrated, with just 5ml treating 250 litres, which is where the value really shows. At 4.8 from over 37,000 ratings, it is about as trusted as aquarium products get. A single bottle treats an enormous volume of water, so even regular water changes barely dent it, making it excellent value over time. Check the current price on Amazon.

Shelf price range checked 26 Sept 2026, 15:37 BST · details

How it compares on the fish & aquatic shelf

We track 50 rated fish & aquatic products, and the middle of that pack scores 4.6 out of 5. This one is on 4.8. Top quarter of the shelf. In an aisle where nearly everything rates well, the distance above the middle is the part worth reading, and this one has it. Weighted for review volume, we place it first on this shelf.

37,365 people rated it, where the shelf median is 3,120. With that many opinions behind it the score won't move much, and it is difficult to manipulate. That is exactly why volume carries weight in our ranking.

The shelf runs from £2.11 to £29.98 and the midpoint is about £8.99. On price, this one is in the top third. It costs more than most and is rated above most, so the premium at least tracks something buyers recognise.

Shelf prices checked 26 Sept 2026, 15:37 BST · details

Worked out from the 50 fish & aquatic products we track, not from the brand's own claims. How we rank →

Key features, as the manufacturer lists them

Taken from the product listing via Amazon's product API. These are the seller's claims, not our test results.

• Neutralises Chlorine and Chloramines
• Reduces Nitrates
• 5ml treats 250Litres
• Value for money
• For freshwater and saltwater aquariums

Check price on Amazon →