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Brightwell MicroBacter Start XLM

Brightwell MicroBacter Start XLM

Regular price $56.99 CAD
Regular price Sale price $56.99 CAD
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Powerful 15x strength live tank starter professional nitrifying bioculture, with far fewer temperature and shelf life restrictions than competitive products, for rapid cycling of new marine and reef fish aquariums and brackish aquariums, and to recover from overcrowding or disasters where the bacteria bed has been damaged or when adding new fish. It is also very useful after rearrangements of scenery or major maintenance work, such as cleaning substrates or biological media to "recharge" the population of nitrifying bacteria.


  • Super concentrated 15X suspension of live non-pathogenic microbes, specially formulated to extremely quickly establish biological filtration in new aquarium setups and to improve the rate of nitrification in existing systems.
  • Useful for quickly restoring nitrifying bacteria in an emergency
  • Especially useful in aquariums with high population density and when adding new fish
  • Useful for restoring nitrifying bacteria after cleaning rocks and surfaces and after using medications.
  • 1. Rapid reduction of ammonia and nitrites.
  • 2. Prevents "new tank syndrome".
  • Supplied in a proprietary base that provides maximum longevity
  • Formulated from extensive data compiled by microbiologists.

The description :

MicrōBacter Start XLM 15X creates a nitrifying biological filter in marine and brackish aquariums of all types and is especially useful for new start-ups, resulting in a cycle of approximately 7 days in most cases if instructions are followed, and no competing bacteria or nothing toxic is added (please read this entire web page.) It quickly removes toxic ammonia and nitrites naturally through non-pathogenic nitrifying bacterial action. Although this product is extremely potent, it can be overdosed up to 5 times the nominal dose in an aquarium emergency. It should be your first choice to dispose of ammonia in an emergency where the filter has been inadvertently killed or in an overcrowding situation.

Technical background:

MicrōBacter Start XLM 15X is a highly concentrated and selective complex of highly effective living microbes and enzymes that rapidly reduce organic nitrogen concentrations - i.e. ammonia and nitrites in marine and brackish ecosystems, which greatly improves water quality and speeds up the cycle. Use of MicrōBacter Start XLM does not eliminate the need for regular partial water changes to help maintain proper concentrations of elements essential for the long-term health and survival of aquarium inhabitants.

Notes - It is normal for lumps to form in the product and the product and the aquarium to have an "earthy" odor or an "off" odor and the aquarium water may become cloudy and the odor and cloudiness may persist for many hours after use. This is due to the bacteria themselves and is an indication of quality and is the reason why it is necessary to shake the product well immediately before using it.

Instructions and guidelines

Important: First, use Brightwell Erase-Cl to completely remove chloramines and chlorine from tap water. Chloramine and chlorine are deadly to bacteria in this product and if not removed will cause it to fail! Shake the product vigorously immediately before using it. Add the appropriate volume of MicrōBacter Start XLM (see below) to the aquarium in a high flow area to promote dispersal. Do not use “live sand” or “dry seeded artificial live rock” until the cycle with this product has been completed for several weeks! (In fact, Brightwell recommends never using dry-seeded artificial "live rock". Best choices are aquaculture live rock, ocean rock, natural cycle artificial rock sold wet, dry artificial rock not sold seeded, Florida dry aragonite, other natural aragonite, marco rock and others Any rock that already contains bacteria and is dry will damage the cycling process and in our experience takes too long to cycle and recycles the wrong nutrients - dry seeded rock will not properly cycle ammonia as it is the wrong species of bacteria)

To seed biological filtration in new aquariums: Add 30 ml (6 capfuls) of MicrōBacter Start XLM per 25 US gallons (95 L) of aquarium water. Add one or more hardy fish. Remove filter socks, turn off UV sterilization and/or ozonation and/or protein skimmer for the duration of the cycle until you are finished dosing this product. Test ammonia and nitrite levels daily or as needed, if either is above 0.2 ppm then you can re-dose MicrōBacter Start XLM at a lower rate of 10 ml per 25 US gallons , if you wish it. At 7 days or more, the tank is cycled if, and only if, the ammonia and nitrite levels are at zero and the nitrate is well above zero. If the ammonia or nitrite levels are above zero, the tank is not yet fully cycled and you should not add fish. if the nitrate is not above zero (at least 0.25 ppm), the tank is not yet fully cycled and you should not add fish.

To replace bacteria killed by thorough cleaning of substrates and surfaces: Add 10 to 30 ml per 25 US gallons (95 L) depending on perceived damage to the filter bed and level of ammonia.

To replace bacteria killed by medication, overcrowding or emergencies: Start by dosing the aquarium with Brightwell Erase Cl to detoxify the ammonia until the bacteria can consume it! Dose daily with Erase Cl as needed to control ammonia until bacteria are completely under control. Add 30 ml per 25 US gallons (95 L) or more of MicroBacter Start XLM, depending on perceived damage to the filter bed. Then add 5ml every half hour until the ammonia levels go down.

To perform a fishless cycle: Purchase a bottle of MicroBacter QuikCyclTM to be used simultaneously with this product, MicrōBacter Start XLM per the QuikCyclTM label. Fishless cycling requires both products to be used together. This product will supply the bacteria and the QuikCycl will supply the nutrients. GO SLOW WITH QuikCyclTM! Any ammonia you put in it will become nitrate which you will need to remove later.

Ongoing maintenance after aquarium cycling: To provide continued biological stability to a cycling aquarium: Switch to MicrōBacterCLEAN once the tank is fully cycled and one week has passed. This will greatly reduce problems during the "ugly phase". At this point you can add Reef BioFuelTM to provide a carbon source for the MicroBacterClean, if desired. If you want to switch to MicrōBacter7, the best time will be when the aquarium has been running for 4-6 months.

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