---
product_id: 311871111
title: "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"
brand: "brightwell aquatics"
price: "3164 som"
currency: KGS
in_stock: false
reviews_count: 5
url: https://www.desertcart.kg/products/311871111-brightwell-aquatics-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick
store_origin: KG
region: Kyrgyzstan
---

# 15x concentrated power scientifically formulated blend cycles tank in 5-7 days 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

**Brand:** brightwell aquatics
**Price:** 3164 som
**Availability:** ❌ Out of Stock

## Summary

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

## Quick Answers

- **What is this?** 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 by brightwell aquatics
- **How much does it cost?** 3164 som with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.kg](https://www.desertcart.kg/products/311871111-brightwell-aquatics-microbacter-start-xlf-concentrated-freshwater-nitrifying-bacteria-quick)

## 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? No Problem:** Optimized for high-density aquariums, effectively reducing toxic ammonia and nitrite spikes.
- • **Fast-Track to Crystal Clear:** Shrimp-safe nitrifying bacteria establish balance in just 5-7 days, beating New Tank Syndrome.
- • **Turbocharge Your Tank Start:** Super concentrated 15x formula accelerates biological filtration for rapid aquarium cycling.
- • **Post-Cleaning Recovery Boost:** Rebuilds beneficial bacteria quickly after substrate cleaning or medication use to keep fish thriving.
- • **Proudly American-Made Quality:** Backed by microbiologists and crafted in the USA for unmatched reliability and longevity.

## Overview

Brightwell Aquatics MicroBacter Start XLF is a 15x concentrated, shrimp-safe nitrifying bacteria solution designed to rapidly establish and maintain biological filtration in freshwater aquariums. It accelerates tank cycling within 5-7 days, reduces harmful ammonia and nitrite levels, and supports high-density fish populations. Ideal for new setups, post-cleaning recovery, and medication aftermath, this American-made formula ensures a stable, vibrant aquatic environment with a shelf life exceeding one year.

## Description

Product 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. 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 volume of MicroBacterStart XLF (see below) to the aquarium in an area of high flow to promote dispersion. Do not use any other bacteria product until cycling with this product is complete. To seed Biological Filtration in new aquaria: Add 30 ml (6 capfuls) of MicroBacterStart XLF per 25 US-gallons (95 L) of aquarium water. Add one or more hardy fish. Remove filter floss, turn UV-sterilization off for the complete period of cycling until you are finished dosing this product. Test ammonia and nitrite levels daily or as needed, if either are above .2 ppm, then you can dose again at a lower dose of 10 ml per 25 US-gallons, if desired. At 7 days or longer, Tank is cycled if, and only if, both ammonia and nitrite levels are zero and nitrate is well above zero. To replace bacteria killed by extensive cleaning of substrates and surfaces: add 10 to 30 ml per 25 US-gallons (95 L) depending on perceived damage to filter bed, and ammonia level. To replace bacteria killed by medications: add 30 ml per 25 US-gallons (95 L) depending on perceived damage to filter bed. Then add 5 ml per half hour until ammonia levels come down. To perform a Fishless Cycle: Purchase a bottle of MicroBacter QuikCycl to use simultaneously with this product, MicroBacterStart XLF. Fishless cycling requires both products to be used together. This product will provide the bacteria and the QuikCycl will provide the nutrients. Do not add fish, inverts or plants until the tank is cycled! Ongoing care After the aquarium is cycled: To provide ongoing biological stability to a cycled aquarium: Switch to FlorinBacterClean or FlorinBacter7 after tank is fully cycled and one week has elapsed. This will greatly reduce problems while the aquarium is maturing. At that point you can add FlorinAxis to provide a carbon source for the FlorinBacter, and plants if desired. Caution: Keep out of reach of children. Not for human consumption. Ingredients: Purified water, proprietary blend of non-pathogenic, beneficial nitrifying microorganisms, proprietary base. Contents: 500 ml (17 fl oz), treats 415 to 1,245 gallons (1,500 to 4,700 liters)

Review: 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.
Review: 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.

## 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 |
|---------------|-------|
| Package Dimensions | 12.19 x 3.91 x 3.71 cm; 140.89 g |
| Item model number | BACSTARTXLF125 |
| Pet Life Stage | All Life Stages |
| Item Form | Liquid |
| Allergen Information | Sulphites Free |
| Size | 125-ml |
| Quantity | 1 |
| Specific Uses | Coat |
| Batteries required | No |
| Item Weight | 141 g |

## Product Details

- **Brand:** Brightwell Aquatics
- **Item form:** Liquid
- **Item weight:** 4.97 Ounces
- **Liquid volume:** 125 Millilitres
- **Manufacturer:** Brightwell Aquatics

## Images

![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 - Image 1](https://m.media-amazon.com/images/I/611mZuJRXKL.jpg)
![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 - Image 2](https://m.media-amazon.com/images/I/81C-8DOHeCL.jpg)
![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 - Image 3](https://m.media-amazon.com/images/I/81tF2dpddsL.jpg)
![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 - Image 4](https://m.media-amazon.com/images/I/91j0HHxHI4L.jpg)
![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 - Image 5](https://m.media-amazon.com/images/I/71kcxnBzFaL.jpg)

## Available Options

This product comes in different **Size** options.

## 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

### ⭐⭐⭐⭐⭐ Review
*by G***️ on 5 December 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.

### ⭐⭐⭐⭐⭐ Review
*by B***E on 17 February 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.

### ⭐⭐⭐⭐⭐ Review
*by M***S on 12 March 2026*

I had been using seachem stability when I started the tank and we were having a few problems like ammonia spikes so I thought I would try this and it got our tank cycled in only two or three days. Its perfect for cycling your tank. I still swear by seachem stability but I learned that stability is more for consistant upkeep of the bacteria rather than Jumpstarting your tank. Overall im very happy with this product!

## 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
- API TAP WATER CONDITIONER Aquarium Water Conditioner 16-Ounce Bottle
- API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, White, Single, Multi-colored

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*Product available on Desertcart Kyrgyzstan*
*Store origin: KG*
*Last updated: 2026-04-22*