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Home » Saltwater Aquarium Supplies  » Filter Media  » Chemical  » Sulfur Media  »  CaribSea L.S.M. Live Sulfur Media 1 Gallon
CaribSea L.S.M. Live Sulfur Media 1 Gallon

CaribSea L.S.M. Live Sulfur Media 1 Gallon

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CaribSea L.S.M. Live Sulfur Media 1 Gallon Information

Here is a pure granular elemental sulfur, with sulfur reducing bacteria right on it. This product can be used in a number of ways, and accomplishes the same job of nitrate reduction as our NO-NO3®. This product is ideal for dual chamber reactors, using our A.R.M.® in one reactor and placing the L.S.M.® in another. This results in a system that delivers elevated calcium, and reduced nitrates.

LSM™ is intended for use in experimental sulfur based nitrate reduction equipment or systems. Nitrate and pH test kits are required to fine tune any nitrate reducing equipment. Sulfur based nitrate reducing bacteria require an oxygen depleted environment. Be aware that this process may strongly acidify surrounding water. A typical system employs two separate canisters with a means to control water flow rate through the reactor. The first canister contains the LSM™. The second canister is filled with aragonite to neutralize acidified water and supply calcium ions as a by-product of neutralization. LSM™ can be placed in any oxygen restricted environment. As with any experimental project, we do not recommend putting a significant amount of sea life at immediate risk, nor risk the health of well established systems without a thorough testing of the effluent parameters first.

Note: Nitrate reduction with sulfur may produce an odor. Due to the experimental nature of sulfur based de-nitrification, the manufacturer accepts no responsibility for the use of this product.

Guidelines for LSMTM Use in Reactors and Modified Jaubert Systems:
The most common application for LSMTM would, of course, be in reaction chambers. Before going into the details here’s a review of the basic concept of autotrophic sulfur denitrification:

In the reactor, sulfur is a food source for bacteria that also eliminate nitrates by converting them to Nitrogen gas. In time the bacteria break down the elemental sulfur and also create sulphate and hydrogen. Both of these by-products can have a negative impact on pH, by bringing the pH down, so it is important to make sure that the effluent from any sulfur reactor is adjusted back to a pH that is acceptable for a marine system.

The most useful reactor designs have a two chamber design with the first chamber holding the sulfur media and performing the denitrification, while the second chamber is filled with calcium reactor media and adjusts the pH of the effluent back to acceptable levels.

Flow rates:
Because autotrophic bacteria will prefer oxygen over nitrate because of this it is important for the flow through the reactor to be slow enough to deplete oxygen so that it is not present for some length of the column. It should also be noted that design is simplified by having a vertical reactor with water added to the bottom so that the sulfur stays in the reactor as it will have a tendency to crumble as it is consumed.

Initial flow rates tend to be in the 1 liter per hour per liter of sulfur in the reactor. Rates may be adjusted up to about 5 liters per hour ultimately but initially should even be below 1 liter.

Because of the slow flow rates, the calcium reactor media may clog as it breaks down too. A coarse grade reactor media will eliminate this possibility. By following these few, loose guidelines a very simple sulfur reactor can be created.

Volume of reactor:
The volume of the Sulfur reactor should be about 1% the volume of the system if the NO3 levels are below 50 mg/l or 2% in systems where the initial concentration is greater than 50 mg/l.

Modified Jaubert sulfur use:
The use of sulfur in a Jaubert or deep sand bed, (DSB), system is even simpler but may not necessarily always be as successful so care should be taken when considering this usage. The product NO NO3TM may be a safer alternative for this type of use as it is tempered a bit by having aragonite mixed with the sulfur beads. In both system types a sulfur media is the bottom substrate, (at the depth of about ½”), either above the plenum or on the tank bottom.

In what type of reactor would I use LSM™?
LSM™ is meant to be used in dual chamber, (or sandwich style single chamber), slow flow, media reactors designed for denitrifying with elemental sulfur. Typically LSM™ is used with ARM™ directly after it to adjust the pH back to sea water parameters. For more information see “Guidelines for the Use of LSM™ in Reactors and Modified Jaubert Systems” in LSM™ Directions.

How does LSM™ work?
LSM™ is a nitrate reducing media for use in low flow sulfur reactors. Bacteria that are on the LSM™ consume elemental sulfur. To do this they need a source of either O2 or NO3. By placing the LSM™ in a slow flow chamber the O2 becomes depleted in the very beginning of the chamber allowing NO3 to be used to complete the digestion of the sulfur in the remainder, (majority), of the chamber. This reduces the NO3 to nitrogen gas and eliminates it from the system.

Manufacturer Info

At CaribSea we take aquariums seriously. Since 1972 we have supplied hundreds of public aquariums, zoos, aquaculture facilities, public and private institutions, and hundreds of thousands of dedicated aquarists with the highest quality marine and freshwater products. CaribSea has been in the forefront of the principle that substrates are a piece of equirment, not just a decorative afterthought. Caribsea substrates are as precisely engineered as any piece of advanced equipment used by today`s hobbyists and professionals. CaribSea products are the chemical support, biological filtration, and biodiversity backbone for many of the most spectacular aquatic displays ever created. We are now celebrating our 35th year in the business, and our product line has continued to grow; making CaribSea your aragonite source and so much more.

CaribSea L.S.M. Live Sulfur Media 1 Gallon Reviews

Average Rating
(12 reviews)
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of 2

Product is not as described

Reviewers Rating Unsatisfactory

Posted: 5/11/2013 from Rainier, OR UNITED STATES
1.0 5
Experience Level: Expert

Comments: This product is not as described. The picture shows granular sulfur that is uniform in shape. The item description is also for granular sulfur. It is not granular sulfur. What you actually get is crushed sulfur that is mostly powder and some large pieces of sulfur. This is not the type of sulfur needed for long term use in a biodenitrator as it becomes packed together and blocks the flow of water causing the production of hydrogen sulfide gas. I would not recommend this product for long term use.

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Reviewers Rating Excellent!

Posted: 11/21/2010 from HARTLAND, WI UNITED STATES
5.0 5
Experience Level: Intermediate


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L.S.M. live

Reviewers Rating Excellent!

Posted: 10/18/2010 from CHESHIRE, MA UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: Works like a charm

0 of 1 People found this review helpful, did you? Yes No

Sulfur Reactor

Reviewers Rating Excellent!

Posted: 6/14/2010 from YUCAIPA, CA UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I purchased LSM on a recomendation for use in a Nitrate Reduction Reactor (NRR) The results, based upon the manufacturer's instructions and use, were as predicted and exceeded my expectations. The Nitrate level in my 100g South African tank was running at approximately 50ppm while all other noteable parameters were stable and safe. I designed and built a NRR and a Calcium Reactor (CR) using Aragonite (ARM)in two separate chambers for serviceability reasons. The effluent output of the combined systems is 0ppm Nitrate and 8.2pH with a slow and steady reduction of Nitrates within the main tank. I recomend LSM to anyone, salt or fresh water, interested in reducing unhealthy levels of Nitrate. Thank you Marine Depot for the valuable and accurate information by which to purchase this product with confidence. Patrick

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Reviewers Rating Excellent!

Posted: 2/14/2010 from CANON, GA UNITED STATES
5.0 5
Experience Level: Expert


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Help for high nitrates

Reviewers Rating Excellent!

Posted: 10/21/2008 from WATERLOO, IL UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: I needed this to help bring down the Nitrates in my aquarium and it's doing the job great. I recommend this product to anyone that is having the same problem, or other problems that this might help.

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Good Product

Reviewers Rating Average

Posted: 10/10/2008 from WALNUT CREEK, CA UNITED STATES
3.0 5
Experience Level: Expert

Comments: This is basically sulfur. Nothing "live" about it. It is a dry product with a lot of fines. I rinsed it in salt water and let it soak with a couple of water changes for two days. Then I put it in my sulfur reactor. It is a good value product and it is working great.

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Works excellent.

Reviewers Rating Excellent!

Posted: 8/1/2008 from KOKOMO, IN UNITED STATES
5.0 5
Experience Level: Intermediate

Comments: On a test 90 Gallon aquarium with approx 200ppm Nitrate (Really high) and 0ppm Nitrite. I used the product in a GEOReef Calcium Reactor. Using about 3/4 Sulfur and 1/4 Aragonite. (I tried smaller quantities and just wasn't getting much result). I started with slow 1 drip per every couple seconds and gradually worked it up by day 3 to a steady fast drip (About 1 cup per 5 minutes). I am getting about 0ppm-5ppm Nitrate and 0ppm Nitrite. At this rate I am processing 20 Gallons a day and project Nitrates to be at about 50ppm after 1 week. Only down side is PH dropped in first day to 7.8 even with drips passing through a collector of additional Aragonite. To counter I had to use a HOT Magnum filter and loaded the Media Cartridge with more Aragonite. That sent my PH back up to 8.1. So make sure you use plenty of Aragonite with this product. Per the instructions this product would work best with 2 seperate reactors.

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CaribSea L.S.M. Live Sulfur Me

Reviewers Rating Great

Posted: 2/21/2008 from SACUL, TX UNITED STATES
4.0 5
Experience Level: Expert

Comments: We use the L.S.M. Live Sulfur Media 1 Gallon as one media in our denitrator that we manufacture. We are very well pleased with quality. This media helps take the nitrates to 0 and produce large amounts of calcium.

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Nitrite reduction

Reviewers Rating Excellent!

Posted: 12/15/2007 from STERLING HEIGHTS, MI UNITED ST
5.0 5
Experience Level: Intermediate

Comments: After only one week this has already begun to reduce my nitrates

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