---
product_id: 209775039
title: "MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 4.22 fl oz"
brand: "brightwell aquatics"
price: "7.39 OMR"
currency: OMR
in_stock: true
reviews_count: 8
category: "Brightwell Aquatics"
url: https://www.desertcart.com.om/products/209775039-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick-start-fish
store_origin: OM
region: Oman
---

# 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, 4.22 fl oz

**Brand:** brightwell aquatics
**Price:** 7.39 OMR
**Availability:** ✅ In Stock

## Summary

> ⚡ Ignite your aquarium’s ecosystem with science-backed speed!

## 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, 4.22 fl oz by brightwell aquatics
- **How much does it cost?** 7.39 OMR with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.com.om](https://www.desertcart.com.om/products/209775039-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

- • **Crowded Tank Champion:** Optimized for high-density aquariums, effectively reducing ammonia and nitrite spikes.
- • **Fast-Track Water Balance:** Shrimp-safe nitrifying bacteria establish a stable, toxin-free environment in under a week.
- • **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 maintenance or medication use.
- • **Proudly American-Made Quality:** Backed by science and crafted in the USA for reliable, 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. It accelerates tank cycling within 5-7 days, supports high-density fish populations by reducing harmful ammonia and nitrite levels, and aids recovery after cleaning or medication. This shrimp-safe, scientifically formulated product is made in the USA and ensures a thriving, balanced aquatic environment.

## 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: Good stuff worth the money - 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.
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 | B086Z6VTJW |
| ASIN  | B086Z6VTJW |
| Age Range Description | All Life Stages |
| Best Sellers Rank | #10,077 in Pet Supplies ( See Top 100 in Pet Supplies ) #78 in Aquarium Water Treatments |
| Brand Name | Brightwell Aquatics |
| Customer Reviews | 4.6 4.6 out of 5 stars (1,302) |
| Date First Available | April 10, 2020 |
| Date First Available  | April 10, 2020 |
| Directions | Important: Do not use this product with untreated tap water. First, use Brightwell Erase-Cl to completely remove chloramines and chlorine from tap water. Chloramine and chlorine are lethal to the bacteria in this product and if not removed will cause it to fail. Shake product vigorously immediately before using. Consult our website for the latest information and cycle schedule. Add the appropriate… |
| Included Components | MicroBacterStart XLF |
| Item Package Dimensions L x W x H | 4.8 x 1.54 x 1.46 inches |
| Item Weight | 4.97 Ounces |
| Item model number | BACSTARTXLF125 |
| Item model number  | BACSTARTXLF125 |
| Manufacturer | Brightwell Aquatics |
| Manufacturer  | Brightwell Aquatics |
| Model Name | MicroBacterStart XLF |
| Package Dimensions  | 4.8 x 1.54 x 1.46 inches; 4.97 ounces |
| Size | 125-ml |
| Specific Uses for Product | Coat |
| Target Audience Keyword | Fish |

## Product Details

- **Brand:** Brightwell Aquatics
- **Item Form:** Liquid
- **Item Weight:** 4.97 Ounces
- **Liquid Volume:** 125 Milliliters
- **Manufacturer:** Brightwell Aquatics

## Images

![MicroBacter Start XLF - Concentrated Freshwater Nitrifying Bacteria - Quick Start Fish Tank Starter, Lift Microbe Levels & Water Filtering - Aquarium Water Treatments, 4.22 fl oz - Image 1](https://m.media-amazon.com/images/I/611mZuJRXKL.jpg)

## Questions & Answers

**Q: I had a major nitrite and nitrate spike. crazy high. my ph was super low, probably the only reason my beta survived. how long will this take to work?**
A: I'm sorry but the person who said it would cycle in 2 days is absolutely wrong. Scientifically that cannot and will not happen. If you educate yourself on the nitogen cycle you will see why. You are right about your ph being super low and your beta surving because the lower your ph is;  less toxic form or ammonium will be present than the more toxic ammonia.

**Q: How long does the water stay cloudy after use?**
A: Once the bacteria begins to bloom , the cloudiness could last a couple weeks . API accu-clear will clear up the cloudiness without affecting the cycle.

**Q: I have nitrogen spikes in my aquarium sometimes after my water changes. Would using this in replacement water be a reasonable preventative or waste $?**
A: This product is hardly a waste of money , I use it in replacement water after every monthly gravel vac to prevent (new water syndrome). My fish seem to instantly detect its presense quicker than Seachems Stability.  Nitrogen prevention , however isn't exactly what this product is for. Yes true , beneficial bacteria products help convert ammonia into nitrite , and then nitrite into harmless nitrate. But the cycle time in which this occurs takes many weeks of patience. If your filter is already cycled , it still takes many days to go through the conversion process. Therefore during a nitrogen spike , you would be better off purchasing Seachems Safe (and be prepared for the white powder substance to smell like sulfur) , this is normal and the answer to your nitrogen problem.

**Q: When it says remove "filter floss" what exactly does it mean?**
A: That means take the filter cartridges out of your filter ........ In other words run it without the carbonated screens that you put in.

## Customer Reviews

### ⭐⭐⭐⭐⭐ 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.

### ⭐⭐⭐⭐⭐ 100 % recommend!!
*by M***A 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.

### ⭐⭐⭐⭐⭐ Multi-purpose
*by Z***Z on June 27, 2024*

I got it to do two things: Keep the water clear in my pond, and help make liquid fertilizer. If you didn't know, you can put grass clippings and other organic stuff into water, and the water will leach out a lot of the good stuff. Eventually this progresses into a fermentation, and finally, nitrization. That's when bacteria start really turning the nitrogen in the liquid into something plants can use. Well, my liquid fertilizer mixture is still sitting, but not long after I added some of this, the water turned black. This is a good sign and shows that everything's working, and quickly! As for my pond, it looks great and has no problems. I recommend this item to people getting into homesteading, aquaculture, regenerative agriculture, making their own fertilizer, etc.

## 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, 4.22 fl oz
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*Product available on Desertcart Oman*
*Store origin: OM*
*Last updated: 2026-02-27*