--- product_id: 245602643 title: "MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 33.8 fl oz" brand: "brightwell aquatics" price: "353 zł" currency: PLN in_stock: true reviews_count: 8 category: "Brightwell Aquatics" url: https://www.desertcart.pl/products/245602643-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick-start-fish store_origin: PL region: Poland --- # 15x concentrated power scientifically formulated blend cycles tank in 5-7 days MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 33.8 fl oz **Brand:** brightwell aquatics **Price:** 353 zł **Availability:** ✅ In Stock ## Summary > ⚡ Fast-track your aquarium’s health with science-backed bacterial power! ## Quick Answers - **What is this?** MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 33.8 fl oz by brightwell aquatics - **How much does it cost?** 353 zł with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pl](https://www.desertcart.pl/products/245602643-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick-start-fish) ## Best For - brightwell aquatics enthusiasts ## Why This Product - Trusted brightwell aquatics brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **High-Density Ready:** Optimized for crowded tanks, effectively reducing ammonia and nitrite even under heavy bioload. - • **Fast-Track Water Balance:** Shrimp-safe nitrifying bacteria establish a stable nitrogen cycle in just 5-7 days, preventing toxic spikes. - • **Turbocharge Your Tank Start:** Super concentrated 15x formula accelerates biological filtration for rapid aquarium cycling. - • **Post-Cleaning Recovery Boost:** Speeds up bacteria re-establishment after tank cleaning or medication use, ensuring fish thrive. - • **Proudly American-Made Quality:** Backed by microbiological research and crafted in the USA for consistent, premium aquatic care. ## Overview Brightwell Aquatics MicroBacter Start XLF is a 15x concentrated nitrifying bacteria solution designed to rapidly establish and maintain biological filtration in freshwater aquariums. Ideal for new setups, high-density tanks, and post-cleaning recovery, it cycles tanks in 5-7 days while safely reducing ammonia and nitrite levels. Made in the USA with a proprietary formula, it supports a thriving aquatic environment for fish and invertebrates alike. ## Description Brightwell Aquatics MicroBacter Start XLF Experience a new level of aquarium care with Brightwell Aquatics MicroBacter Start XLF – the ultimate solution for achieving a balanced and thriving aquatic environment. Our concentrated formula is designed to boost the nitrogen cycle in your aquarium, ensuring the rapid establishment of biological filtration and creating a stable habitat for your aquatic companions. It’s particularly useful for new startups, resulting in tank cycling in 5 to 7 days in most cases. This shrimp safe advanced blend works effectively to break down organic waste, keeping your aquarium water pristine. It is meticulously formulated to enhance water quality and eliminate ammonia and nitrite spikes. Whether you're setting up a new tank or maintaining an established one, MicroBacter Start XLF is your go-to solution. Its versatility extends to fish and invertebrate freshwater aquariums and is particularly effective for live planted aquariums, providing powerful support for a diverse range of aquatic environments. FEATURES AT A GLANCE Super concentrated 15x strength formula Useful for rapidly re-establishing nitrification bacteria in case of an emergency Usually cycles in 5-7 days Ideal in aquaria with high population densities and when adding new fish Best used post-cleaning of rocks and surfaces or after use of medication Prevents “New Tank Syndrome” Supplied in a proprietary base for maximum longevity Formulated utilizing extensive data compiled by microbiologists AMERICAN-MADE EXCELLENCE Trust in the quality and excellence of Brightwell Aquatics, an industry-leading brand committed to providing innovative and scientifically backed aquatic care products. Made in the USA, we consistently strive to deliver advanced superior quality solutions to elevate the vibrancy and health of your aquarium. Review: Great bacteria booster for starting and supporting a cycle - I’ve had very good results using Brightwell Aquatics MicroBacter alongside cycled or seeded bio media. Using both together really helps fast track the cycling process instead of starting from zero. It’s easy to dose and has been especially helpful when setting up new tanks or reinforcing an existing cycle after changes. Pairing it with established media has made cycling much quicker and less stressful. I like keeping it on hand for both new setups and ongoing tank maintenance. Review: 100 % recommend!! - Amazing product!! My tank was cycling for over a month and no changes, my ammonia 0ppm, nitrite super high and barely any nitrate, and I was using brightwell florin bacter 7 which is great as well but for some reason wasn’t working for this bigger tank. So I did some research and it said I could just substitute the florin Bacter for the micro bacter start XLF since they’re the same brand and are compatible (do your research) so I did and after 4 days dosing it my tank was ready and no nitrites at all!! It was like magic. I recommend this to start cycling the tank since it’s so strong and then continue after water changes with the Florin Bacter7 which is what I’m doing and it’s going great so far. Also keep both in the fridge. One think I must add is that for some reason I thought the bottle was going to be bigger because of the picture they display but it’s still enough because it’s concentrated and it’s only to use once in a while. I also use it when I have ammonia in my nano tank I dose it for 2-3 days and it boosts the nitrifying bacteria 🙌🏻 love it and will buy again and again. ## Features - HIGH-POWER TANK STARTER – MicroBacter Start XLF is a powerful 15x concentrated blend designed to kickstart biological filtration in new tanks and existing freshwater aquariums. It enhances water quality, providing a flourishing underwater environment with live, non-pathogenic microbes - RAPID WATER CYCLING – Optimize your aquarium’s health swiftly with this shrimp safe fast-acting solution. Quickly accelerate the tank's beneficial nitrifying bacteria population for balance and stability in just 5-7 days. It’s the ideal solution when time is crucial - FOR HIGH-DENSITY AQUARIUMS – A scientifically blended formula that caters to crowded tanks and effectively reduces ammonia and nitrite levels, all while supporting population density. Supplied in a proprietary base, providing maximum longevity in shipping and in your aquatic ecosystem. It has a shelf life of over a year at room temperature. - ADVANCED TANK RECOVERY – Perfect for all levels of aquarium enthusiasts and compatible with various sand and rock substrates. Best used post-cleaning or after use of medications. This ammonia remover accelerates the re-establishment rate of fish tank bacteria, ensuring your fish thrive - AMERICAN-MADE EXCELLENCE – Brightwell Aquatics is an industry-leading brand committed to providing innovative and scientifically backed aquatic care products. Made in the USA, we consistently deliver advanced superior quality solutions to elevate the vibrancy and health of your aquarium ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B086Z669LW | | ASIN | B086Z669LW | | Allergen Information | Sulphites Free | | Best Sellers Rank | #8,784 in Pet Supplies ( See Top 100 in Pet Supplies ) #63 in Aquarium Water Treatments | | Brand Name | Brightwell Aquatics | | Customer Reviews | 4.6 4.6 out of 5 stars (1,342) | | Date First Available | April 10, 2020 | | Included Components | MicroBacterStart XLF | | Item Form | Liquid | | Item Type Name | Water Conditioner | | Item Weight | 1.11 Kilograms | | Item model number | BACSTARTXLF1L | | Liquid Volume | 1 Liters | | Manufacturer | Brightwell Aquatics | | Manufacturer | Brightwell Aquatics | | Manufacturer Part Number | BACSTARTXLF1L | | Model Number | BACSTARTXLF1L | | Package Dimensions | 9.06 x 3.46 x 3.03 inches; 2.45 Pounds | | Target Species | Fish | | UPC | 810086019625 | | Unit Count | 1 Count | ## Product Details - **Brand:** Brightwell Aquatics - **Item Form:** Liquid - **Item Weight:** 1.11 Kilograms - **Liquid Volume:** 1 Liters - **Manufacturer:** Brightwell Aquatics ## Images ![MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 33.8 fl oz - Image 1](https://m.media-amazon.com/images/I/71dD74US-oL.jpg) ## Available Options This product comes in different **Size** options. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great bacteria booster for starting and supporting a cycle *by B***E on February 17, 2026* I’ve had very good results using Brightwell Aquatics MicroBacter alongside cycled or seeded bio media. Using both together really helps fast track the cycling process instead of starting from zero. It’s easy to dose and has been especially helpful when setting up new tanks or reinforcing an existing cycle after changes. Pairing it with established media has made cycling much quicker and less stressful. I like keeping it on hand for both new setups and ongoing tank maintenance. ### ⭐⭐⭐⭐⭐ 100 % recommend!! *by G***️ on December 5, 2025* Amazing product!! My tank was cycling for over a month and no changes, my ammonia 0ppm, nitrite super high and barely any nitrate, and I was using brightwell florin bacter 7 which is great as well but for some reason wasn’t working for this bigger tank. So I did some research and it said I could just substitute the florin Bacter for the micro bacter start XLF since they’re the same brand and are compatible (do your research) so I did and after 4 days dosing it my tank was ready and no nitrites at all!! It was like magic. I recommend this to start cycling the tank since it’s so strong and then continue after water changes with the Florin Bacter7 which is what I’m doing and it’s going great so far. Also keep both in the fridge. One think I must add is that for some reason I thought the bottle was going to be bigger because of the picture they display but it’s still enough because it’s concentrated and it’s only to use once in a while. I also use it when I have ammonia in my nano tank I dose it for 2-3 days and it boosts the nitrifying bacteria 🙌🏻 love it and will buy again and again. ### ⭐⭐⭐⭐⭐ Good stuff worth the money *by K***N on September 25, 2025* Absolute best way to start your tropical fish tank and have a perfect environment for fish survival. This stuff is a must and it works well. ## Frequently Bought Together - Brightwell Aquatics MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 33.8 fl oz - Fluval BioMax Biological Material Remover, 500 g - Biological Filter Media for Aquariums - Fluval Carbon Filter Media for Aquariums, Premium Bituminous Carbon Inserts, 100-gram Nylon Bags, 3 Count (Pack of 1), A1440 --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.pl/products/245602643-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick-start-fish](https://www.desertcart.pl/products/245602643-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick-start-fish) --- *Product available on Desertcart Poland* *Store origin: PL* *Last updated: 2026-04-26*