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Seachem Prime 250ml

Price:  11.49

Aqua points: 11 [read more]
Stock: In stock
Model: 020042
Manufacturer: Seachem


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Prime is the complete and concentrated conditioner for both fresh and salt water. Prime removes chlorine, chloramine and ammonia. Prime converts ammonia into a safe, non-toxic form that is readily removed by the tank’s biofilter. Prime may be used during tank cycling to alleviate ammonia/nitrite toxicity. Prime detoxifies nitrite and nitrate, allowing the biofilter to more efficiently remove them. It will also detoxify any heavy metals found in the tap water at typical concentration levels. Prime also promotes the production and regeneration of the natural slime coat. Prime is non-acidic and will not impact pH. Prime will not overactivate skimmers. Use at start-up and whenever adding or replacing water.

Why It's Different
Nearly all companies manufacture a product that removes chlorine. None of those, however, can compare in quality, concentration, or effectiveness to Seachem’s flagship product: Prime. Prime is the second most concentrated dechlorinator on the market after our own aquavitro alpha. A single 100 mL bottle will treat 1000 US gallons of tap water. Prime will remove both chlorine and chloramines from municipal water supplies. 

Prime also contains a binder which renders ammonia, nitrite, and nitrate non-toxic. It is very important to understand how those two functions work together. All dechlorinators operate through a chemical process known as reduction. In this process, toxic dissolved chlorine gas (Cl2) is converted into non-toxic chloride ions (Cl-). The reduction process also breaks the bonds between chlorine and nitrogen atoms in the chloramine molecule (NH2Cl), freeing the chlorine atoms and replacing them with hydrogen (H) to create ammonia (NH3).

Typically, dechlorinators stop there, leaving an aquarium full of toxic ammonia! Seachem takes the necessary next step by including an ammonia binder to detoxify the ammonia produced in the reduction process.

Be very careful when purchasing water conditioners. If your municipality includes chloramines in the water supplies, a standard sodium thiosulfate dechlorinator is not enough. Prime promotes the natural production and restoration of the slime coat rather than relying on artificial or non-native slime compounds. A further bonus for the reef hobbyist—Prime will not overactivate protein skimmers.

Use 1 capful (5 mL) for each 200 L (50 gallons*) of new water. This removes approximately 1 mg/L ammonia, 4 mg/L chloramine, or 5 mg/L chlorine. For smaller doses, please note each cap thread is approx. 1 mL. May be added to aquarium directly, but better if added to new water first. If adding directly to aquarium, base dose on aquarium volume. Sulfur odor is normal. For exceptionally high chloramine concentrations, a double dose may be used safely. To detoxify nitrite in an emergency, up to 5 times normal dose may be used. If temperature is > 30C and chlorine or ammonia levels are low, use a half dose.

Date Added: 01/06/2016 by Alexis Dixon

quick delivery and great product. Best water conditioner there is.

Date Added: 27/04/2016 by Alexis Dixon

Fast delivery. Simply the best water conditioner. My shrimp in particular don't like anything else being used. Only need tiny amount so lasts for ages.

Date Added: 11/04/2016 by Douglas Hawke

IRecommend this product.

Date Added: 09/02/2015 by Peter Copestake

I've not yet used this particular delivery but I have used the product in the past and it is by far the best make on the market even though there are others claiming to do mor eor less the same thing. highly recommended

Date Added: 18/11/2014 by Mark Stockton

I first purchased this to re-active my Seachem Purigen which is a great product by the way, but have since started to use it whenever I do my water changes, its a great product and for those on a budget works out a lot cheaper than the other well known products found in most high street aquatic stores as a 5ml cap treats 200l.

Date Added: 06/10/2014 by Pamela Fergusson

Prime is the most effective and economical water conditioner that I have come across to date.

Date Added: 19/06/2014 by Craig Magee

It's Prime! It's tried and tested. It works. Stop reading this and just buy it already.

Date Added: 14/06/2014 by Lesley Waters

This is my second purchase of Prime - I won't use anything else now - it's wonderful and very economical. Delivery was quick as usual!

Date Added: 29/10/2013 by Paul Bailey

great product and great swift service thankyou

Date Added: 24/10/2013 by Paul Bailey

great product well packaged and swift delivery thankyou

Date Added: 18/06/2013 by Kasey Kemp

Only need to use 5ml per 200l of water so is lasting for ages. No problems so far

Date Added: 15/04/2013 by Andre Jacobs

Forget all the other water conditioners. Over years of being in the hobby (in different countries as well) I have used almost every water conditioner out there until I found Seachem Prime. This product will save you lots and lots of since you use very little with every water change. Best is this isn't some horrible colour (like the blue ones) that change the colour of your water or stain your silicone seals. I do weekly 50% water changes on a 120L and 50L aquariums and a 250ml bottle lasts me a year. Also if you clean stuff (e.g. co2 diffusers) with bleach (strong chlorine based) then you can use this to instantly make the items safe again for the aquarium (but always rinse well before hand too just to be safe)

Date Added: 01/05/2012 by Sally Lewis

Prime and its powder form Safe are water conditioners I have just for years. In my opinion one of the best on the market, never let me down and great in a emergency if you have a spike. A product every fish cupboard should have :)

Ask a question about this product
I urgently need some prime as i knocked my bottle over and lost the lot!! I seen somewhere you have a shop in exeter?? If so where?? I cant rely on postal service at moment as need tomorrow plus tight for cash so only option to find a shop. Thanks Matt


We're not open on weekends - sorry

HI, I use reverse osmosis water could prime seachem be added as well


Yes it could but what would you need prime for?

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