Biopellets – A Beginner’s Guide

What are biopellets?

Biopellets are a biodegradable polymer that is made from bacteria. They act like steroids for the beneficial bacteria in your system. You want a strong colony of this bacteria because it naturally controls the nitrates in a tank. Corals need some small levels of nitrates and phosphates to thrive. But too much of either can lead to problems like coral death or algae bloom.

Biopellets provide an ideal environment for beneficial bacteria to thrive. By pumping water from your system into a biopellet reactor we are creating a controllable, food-filled environment where bacteria can live and reproduce.

Biopellet Alternatives

Biopellets provide a source of carbon, but not the carbon like media that removes toxins and impurities. This type of carbon is more of a building block for life.

Vodka dosing, carbon additives (such as Red Sea NO3:PO4-X), sugar and even vinegar are all ways to add carbon. Adding these elements to the system by dosing turn the entire tank into an ideal environment for the bacteria.

Should I Use Biopellets?

If there are so many alternatives to biopellets, why would you use them? Biopellets do a very good job at lowering nitrates and phosphates when used with a protein skimmer. Because of this, hobbyists are able to stop using GFO (Granulated Ferric Oxide). Unlike GFO, biopellets only need to be “topped off”, rather than changed out completely, as they are consumed by the bacteria. This allows hobbyists to have less maintenance on their tank and still be able to maintain crystal clear water and pristine water parameters.

Hobbyists will see the best performance from using biopellets on systems that have a heavy biological load. Those of us who have a lot of fish or tend to feed heavy (or a mixture of both) have probably dealt with problems that this can cause. A bloom of algae or cloudy water, as well as less-than-ideal growth from our corals are common effects from heavy stocking. 

Avoiding Biopellet Problems

Saying that biopellets have problems is a bit misleading. In almost every case that I’ve seen where people have problems, they come from couple of specific issues:

  • Using the full amount of biopellets from day one, causing a sudden drop in levels, leading to system shock.

  • Not having an effective protein skimmer to remove excess waste from the water.

How do you avoid these problems?

It’s important to remember the biggest rule of saltwater aquariums – stability is key. Hobbyists tend to run into problems when they “chase numbers” and make drastic changes rather than providing a stable environment. Because biopellets are used to control levels, it’s easy to get into the bad habit of looking for perfection.

Getting Started With Biopellets

What we’re aiming for is a gradual reduction of nitrates. To do this, we need to start with 1/4 or 1/2 the recommended amount of biopellets in the reactor. Let the correct amount of biopellets soak in RO water for 24 hours. This will assure that when you put your biopellets in your reactor that they start to tumble right away and not float to the top of your reactor. Set your pump to gently tumble the pellets in the reactor. If they are allowed to be stationary, they can stick to one another. Allow the bacteria a couple of weeks to colonize the pellets, and make sure that you’re using an accurate test kit every few days.

After a couple of weeks have passed, and your level drop starts to plateau, add another small amount of pellets. We are doing this to continue having as low decrease in nitrates and phosphates. Keep testing your water and looking for another plateau. Once your parameters are in an acceptable range, this should roughly be the amount you want to keep your biopellet reactor at.

The other important aspect about biopellets is skimming. As the bacteria starts consuming the biopellets, a type of film will be covering the biopellet. As the pellets tumble and bounce off each other this is rubbed off and exported by your skimmer. This is also good to note that you want your out tube of your biopellet reactor to run in close area to your skimmer so you wont have a lot of excess film in your water column. This could potentially lead to lager or cyan outbreaks.




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