Aquarium product reviews Featured Articles Main Slider Maintenance and cleaning Water chemistry

The best Aquarium Water conditioner? – Quantum Freshwater UK

the best aquarium water conditioner quantum freshwater UK aquarium water changes

Water conditioners are essential for most aquariums. Tap water contains chlorine, which isn’t good for our fishy friends. Most water conditioners will remove chlorine and some will do much more than that. We’ve taken a look at Quantum Freshwater’s Water Primer, here’s what we thought…

The best aquarium water conditioner

A common question amongst aquarists is, what is the best aquarium water conditioner?

A water conditioner is an essential part of keeping fish for most aquarists and there are loads on the market, but which one is the best?

For years, I have been using Seachem Prime, it has always stood well above the rest in my opinion as it is more concentrated (meaning you use less and it goes further) and has the added benefits of removing certain nasties from your water. Helping to keep your fish healthy.


best aquarium water conditioner


The concentration is handy when you have a big aquarium, some brands of dechlorinator would require a whole bottle to treat my largest aquarium, so it isn’t cost-effective and they don’t have the additional benefits.

There’s no doubt in my mind that Seachem Prime is a great water conditioner. But recently I came across another product that grabbed my attention, one I hadn’t used before which is from the UK.

So after it caught my attention, I ordered a bottle straight away, as I was fairly sure that I could have just found the new best aquarium water conditioner.

That product is made by Quantum freshwater UK.


Quantum UK water primer

There were several reasons why Quantum freshwater UK’s water primer grabbed my attention:

  • It says it does everything that prime does.
  • It is even more concentrated than prime is.
  • It is from the UK!
So what does it do?

Here is the full description for Quantum’s water primer from Quantum freshwater UK themselves:

Removes/Detoxifies Chlorine, Chloramine, Ammonia, Nitrite, Nitrate & Heavy Metals.

For Freshwater & Saltwater Use

Water Primer™ is designed to remove/detoxify Ammonia, Chlorine, Chloramine, Nitrite, Nitrate & Heavy Metals that may cause harm to your aquarium.

Chlorine & Chloramine present in tap water, while Ammonia, Nitrate & Nitrate are by-products from fish waste and organic decay.

These can cause harm and even death to your aquarium’s inhabitants at high concentrations.

Water Primer™ renders tap water safe for use in aquariums and can potentially save your aquarium from a wipeout due to an ammonia or nitrite spike.


–Deionised Water

– Blend of Ammonia, Chlorine, Chloramine, Nitrite, Nitrate & Heavy Metal removing/detoxifying salts


quantum freshwater UK best aquarium water conditioner


So, not only will this remove/detoxify chlorine from your tap water, but it could also remove/detoxify chloramines, ammonia, nitrite, nitrate and even any heavy metal content your water may have in it. This is great for your fish and will help to keep your aquarium cleaner and healthier for longer.

Ammonia and Nitrite are all waste products produced by your fish that become deadly very quickly. Your filter media holds bacteria which converts them into nitrate which is far less toxic, but still lethal in high enough doses.

Should your filter fail to convert these for any reason, they can quickly build up in your aquarium and cause harm, if not death to your fish.

This water conditioner could act as a backup, so any Ammonia, Nitrite or Nitrate that builds up is detoxified. This means that should you suffer the occurrence of a spike, it may save your fish’ lives.

Unfortunately, I don’t have a Chemistry lab at home, nor would I know where to even start on testing what it actually does to Ammonia and Nitrite. As my tanks are very mature, I never detect any on tests anyway, but what I could test it on is Nitrate.

I waited until the day before water change day on my CA tank, this tank is well stocked so by the time I get to my weekly water change it is usually approaching 20ppm of Nitrates. This is what the test showed before I added a double dose (20ml) of Quantum water primer.

The next day, before starting my water change I tested the water again. Nitrates had roughly halved, meaning that actually, if I had needed to, I could have left the water change for a few more days.

(After searching the internet I cannot find any scientific data on any dechlorinators ability to remove/detoxify ammonia or nitrite. Therefore I cannot confirm if the claims of this ability are true).

Quantum freshwater UK primer, as I mentioned, is more concentrated than prime. Seachem prime requires 5ml for every 200 litres of aquarium volume. This is pretty concentrated and means that a bottle goes a long way, especially compared to other brands.

Quantum freshwater UK water primer requires 5ml used for every 300 litres of aquarium water. This means that it goes even further.

Price comparison of the best aquarium water conditioners

In my opinion, the two products I have mentioned are the two best water conditioners that are currently available, so, how do they compare in price.

For a fair test, and easy maths, I have compared the 1-litre bottle of each product on

Product Price for 1L Water volume treated. (Standard dose). Remarks
Seachem Prime £33.99 (currently on offer for £30.25) 40,000L
Quantum freshwater UK water primer £27.99 60,000L UK based Company


As you can see, the table above is relatively simple and speaks for itself. These two water conditioners are both amazing products, but Quantum is lower in price and goes further, making a bigger saving overall.

Whilst the fact that Quantum is a UK company has no effect on the quality of the product, I’ve included it in the remarks, as being from the UK myself, I do like to support UK companies.

So, after using Quantum water primer, and Seachem prime, and many other products in the past, would I say that Quantum UK has made the best aquarium water conditioner?


The best aquarium water conditioner?

It takes a real fish nerd like myself to get excited over a new water conditioner, but admittedly, I did.

The bottle looks great and this stuff is well priced, especially considering that a 1-litre bottle will treat up to 60,000 litres of water. For a 200 litre aquarium, that means 1200 25% water changes, or 600 50% water changes are covered for a cost of £27.99. That’s great value and it will last ages!

It does have one minor drawback though:

It isn’t as widely available in shops yet as Prime is. If I need a bottle of water conditioner, I can walk into just about any aquarium shop and grab a bottle of prime.

This isn’t the case for Quantum primer yet. Their retailer search at the time of me ordering showed no shops that stocked Quantum within 50 miles of me. That has now changed and there are 3 showing up, so it is improving.

With Amazons speedy deliveries though, the fact it isn’t in local shops really is a minor issue and as long as you don’t suddenly realise you have run out halfway through a water change, it won’t cause you a problem.


So, overall I would say that yes, this is now the best aquarium water conditioner on the market in the UK and I will certainly be continuing to use it.

I’ve been using this for a few weeks now on all of my tanks and I have been nothing but happy with it. I’ve had no problems after switching products and my fish are all happy and healthy.


This is a great product and will certainly help to keep your aquarium, and fish, extra healthy. The additional effects of detoxification and removal of harmful substances in the water really is a great addition to a water conditioner.


So if you would like to order a bottle for yourself, here are the UK links:

1L Quantum freshwater UK water primer


To see more products from Quantum freshwater UK, use the link below:

All Quantum products

(As an Amazon Associate, I earn on qualifying purchases.)


If you’re in the USA, you can get yourself a bottle of Quantum too, along with all their other products, use the link below for the US site:

Quantum – USA


(Diclaimer – This review is not paid or sponsored. All my reviews are my own opinion and have not been influenced in any way.)


Found this article useful? Check out the rest of our blog page HERE.



About the author

James @Seriously Fishy

I am a fish keeping enthusiast with over 20 years experience. I currently keep American Cichlids (CA) which are my favourite fish to keep so far. I started Seriously Fishy as I noticed a large volume of people on various web pages looking for help with Aquarium basics. I created the first Seriously Fishy book to solve the issue in 28 pages, that led to the Seriously Fishy UK fish forum and blog.

Leave a Comment