--- product_id: 1627531 title: "NO3:PO4-X 500ml NOPOX - Nitrate & Phosphate Reducer for Reef Aquariums, Promotes Healthy Coral Growth, Controls Algae & Maintains Water" brand: "red sea" price: "€ 61.00" currency: EUR in_stock: true reviews_count: 13 url: https://www.desertcart.hr/products/1627531-no3-po4-x-500ml-nopox-nitrate-and-phosphate-reducer-reef store_origin: HR region: Croatia --- # reduces nitrates & phosphates effectively promotes vibrant coral & algae control 500ml potent liquid formula NO3:PO4-X 500ml NOPOX - Nitrate & Phosphate Reducer for Reef Aquariums, Promotes Healthy Coral Growth, Controls Algae & Maintains Water **Brand:** red sea **Price:** € 61.00 **Availability:** βœ… In Stock ## Summary > 🌟 Elevate your reef gameβ€”clear water, happy corals, zero compromises! ## Quick Answers - **What is this?** NO3:PO4-X 500ml NOPOX - Nitrate & Phosphate Reducer for Reef Aquariums, Promotes Healthy Coral Growth, Controls Algae & Maintains Water by red sea - **How much does it cost?** € 61.00 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/1627531-no3-po4-x-500ml-nopox-nitrate-and-phosphate-reducer-reef) ## Best For - red sea enthusiasts ## Why This Product - Trusted red sea brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Trusted US-Made Quality:** Proudly manufactured in the USA, ensuring premium standards and reliability. - β€’ **Easy Daily Dosing System:** Simplifies carbon dosing with clear instructions, perfect for busy reef keepers. - β€’ **Algae Management Made Simple:** Effectively curbs algae outbreaks, keeping your aquarium pristine and Instagram-ready. - β€’ **Enhanced Coral Health & Growth:** Boosts polyp extension and coral vibrancy for a thriving underwater ecosystem. - β€’ **Precision Nitrate & Phosphate Control:** Scientifically formulated to lower harmful nutrients and maintain crystal-clear reef water. ## Overview Red Sea NO3:PO4-X is a 500ml liquid aquarium supplement designed to biologically reduce nitrates and phosphates, promoting healthier coral growth and controlling algae in reef tanks. Made in the USA, it simplifies carbon dosing with easy-to-follow instructions, helping reef enthusiasts maintain optimal water clarity and nutrient balance for vibrant aquatic life. ## Description Red Sea Fish Pharm ARE22203 NO3: PO4-X Biological Nitrate and Phosphate Reducer for Aquarium, 500ml Review: Seems to be effective, but READ the instructions completely - I recently suffered a massive system crash due to high phosphates leaching into my topoff water from the reservoir. I decided to add Red Sea NO3:PO4-X Nitrate & Phosphate Reducer to my repair plan and just see how it went. Now, bear in mind that this was just ONE PART of a multi-step battle plan, so I can't say for sure what worked better, or if anything was useless, or if this was all just blind luck by a dumb guy with a tank, but who knows. I do think it helped, so here's my review: Naturally, desertcart shipping was quick. I read the rest of the reviews, some good, some bad, and decided to give it a go. First off, be sure to read the entire instruction packet. It might seem silly, but there are different dosing regimens for different things you want to do to your tank, so read 'em. When I opened the bottle, I was assaulted by the heady aroma of vinegar and....SOMETHING. Something alcoholic, I think. Yep, you guessed correctly....this stuff is basically a "proprietary blend" of carbon sources. In other words, this is carbon-dosing for idjits. I have no problem with this. I have been afraid of carbon dosing because it seems too fiddly. This product dumbs it down for the rest of us and makes it a relatively easy task. The only thing you need to know about carbon dosing, though, is that once you start, you need to make sure it's done daily. If you decide to stop you need to wean the tank off of it. It's going to promote extra bacterial growth, which will in turn metabolize phosphates and nitrates and bring those terrifying numbers back into an acceptable range. The product claims that this will also promote clarity of the water and greater polyp extension. Well, it's been a few weeks since I started, and I can definitely see a lot of improvement. Dunno if it's the GFO, the UV filter, the massive water change, the Red Sea Reducer, or (most likely) a combination off all of the above. But I DO see much clearer water and coral polyp extension has been great, so I'm gonna go ahead and call that a win for this particular product. My phosphates have dropped from 0.18 on a Hanna checker down to 0.02, and my tank is back to happy again. I'd recommend this product, but I want people to be aware that this IS a carbon dosing source, and those instructions have to be fully read and understood before you start. Review: It really works! - It took a while to arrive and based on what I read online I started slowly using about 1/2 the recommended dosage. It worked a little, so I increased the dosage to recommended levels. Wow! It works great and has reduced the nitrate level in my fish only tank considerably and my algae problem is under control. Note, I dosed by hand daily as I do not have a dosing pump. ## Features - Country Of Origin: United States - The Package Length Of The Product Is 3 Inches - The Package Width Of The Product Is 3 Inches - The Package Height Of The Product Is 8 Inches ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B006L48D3U | | Allergen Information | Cashews Free | | Best Sellers Rank | #105,736 in Pet Supplies ( See Top 100 in Pet Supplies ) #963 in Aquarium Water Treatments | | Brand | Red Sea | | Brand Name | Red Sea | | Customer Reviews | 4.6 out of 5 stars 578 Reviews | | Global Trade Identification Number | 00730773222032 | | Included Components | PHL306049 | | Item Form | Liquid | | Item Type Name | aquarium supplement | | Item Weight | 16 ounces | | Liquid Volume | 500 Milliliters | | Manufacturer | TopDawg Pet Supply | | Manufacturer Part Number | 306049 | | Model Number | 306049 | | Pet Type | Fish | | Target Species | Fish | | UPC | 730773222032 | | Unit Count | 16.9 Fluid Ounces | ## Product Details - **Brand:** Red Sea - **Item Form:** Liquid - **Item Weight:** 1 Pounds - **Liquid Volume:** 500 Milliliters - **Manufacturer:** TopDawg Pet Supply ## Images ![NO3:PO4-X 500ml NOPOX - Nitrate & Phosphate Reducer for Reef Aquariums, Promotes Healthy Coral Growth, Controls Algae & Maintains Water - Image 1](https://m.media-amazon.com/images/I/616rw6PL5yL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Seems to be effective, but READ the instructions completely *by R***D on February 23, 2014* I recently suffered a massive system crash due to high phosphates leaching into my topoff water from the reservoir. I decided to add Red Sea NO3:PO4-X Nitrate & Phosphate Reducer to my repair plan and just see how it went. Now, bear in mind that this was just ONE PART of a multi-step battle plan, so I can't say for sure what worked better, or if anything was useless, or if this was all just blind luck by a dumb guy with a tank, but who knows. I do think it helped, so here's my review: Naturally, Amazon shipping was quick. I read the rest of the reviews, some good, some bad, and decided to give it a go. First off, be sure to read the entire instruction packet. It might seem silly, but there are different dosing regimens for different things you want to do to your tank, so read 'em. When I opened the bottle, I was assaulted by the heady aroma of vinegar and....SOMETHING. Something alcoholic, I think. Yep, you guessed correctly....this stuff is basically a "proprietary blend" of carbon sources. In other words, this is carbon-dosing for idjits. I have no problem with this. I have been afraid of carbon dosing because it seems too fiddly. This product dumbs it down for the rest of us and makes it a relatively easy task. The only thing you need to know about carbon dosing, though, is that once you start, you need to make sure it's done daily. If you decide to stop you need to wean the tank off of it. It's going to promote extra bacterial growth, which will in turn metabolize phosphates and nitrates and bring those terrifying numbers back into an acceptable range. The product claims that this will also promote clarity of the water and greater polyp extension. Well, it's been a few weeks since I started, and I can definitely see a lot of improvement. Dunno if it's the GFO, the UV filter, the massive water change, the Red Sea Reducer, or (most likely) a combination off all of the above. But I DO see much clearer water and coral polyp extension has been great, so I'm gonna go ahead and call that a win for this particular product. My phosphates have dropped from 0.18 on a Hanna checker down to 0.02, and my tank is back to happy again. I'd recommend this product, but I want people to be aware that this IS a carbon dosing source, and those instructions have to be fully read and understood before you start. ### ⭐⭐⭐⭐⭐ It really works! *by M***. on February 12, 2025* It took a while to arrive and based on what I read online I started slowly using about 1/2 the recommended dosage. It worked a little, so I increased the dosage to recommended levels. Wow! It works great and has reduced the nitrate level in my fish only tank considerably and my algae problem is under control. Note, I dosed by hand daily as I do not have a dosing pump. ### ⭐⭐⭐⭐⭐ It really works!! *by J***N on August 20, 2016* Heard nothing but good stuff about this. I had problems with high nitrates in my predator fowlr tank. I didn't want to do macro of biopellets. Besides I heard this stuff work much better and faster. I got 100 g DT and 55 sump. I called red sea and they gave me the info I needed for how much to dose my tank, depending on your nutrients levels. I'm dosing the max dose 3ml per 25 gallons. Its been a week since I've started dosing and my nitrates were at 80ppm before dosing. Now there at 20a week after dosing. I have a yellow head moray eel and Him alone is a big bio load. I'm already satisfied with results and it haven't been a month of using this product. I don't need undetectable nitrates But under 20 I can live with. I'll be using this as long as im in the marine hobby. ## Frequently Bought Together - Red Sea NO3:PO4-X 500ml NOPOX - Nitrate & Phosphate Reducer for Reef Aquariums, Promotes Healthy Coral Growth, Controls Algae & Maintains Water - Red Sea Reef Energy Plus 500ml (AB+) All in One Coral Food for Saltwater Aquarium Marine Reef Tanks | Food for Soft, LPS, SPS, and Non-Photosynthetic Corals - Tropic Marin All-for-Reef Liquid 500 ml. --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.hr/products/1627531-no3-po4-x-500ml-nopox-nitrate-and-phosphate-reducer-reef](https://www.desertcart.hr/products/1627531-no3-po4-x-500ml-nopox-nitrate-and-phosphate-reducer-reef) --- *Product available on Desertcart Croatia* *Store origin: HR* *Last updated: 2026-06-25*